diff --git a/CMakeModules/FindMPI.cmake b/CMakeModules/FindMPI.cmake
index 8b75eee..42bdd7a 100644
--- a/CMakeModules/FindMPI.cmake
+++ b/CMakeModules/FindMPI.cmake
@@ -145,6 +145,8 @@ macro(clearFindMPIVariables)
     unset(MPIEXEC_PREFLAGS CACHE)
     unset(MPIEXEC_POSTFLAGS CACHE)
     unset(MPIEXEC_MAX_NUMPROCS CACHE)
+    unset(MPI_LIBRARY CACHE)
+    unset(MPI_EXTRA_LIBRARY CACHE)
 endmacro()
 
 # include this to handle the QUIETLY and REQUIRED arguments
@@ -233,7 +235,7 @@ set(_MPI_EXEC_NAMES mpiexec mpirun lamexec srun)
 # For 64bit environments, look in bin64 folders first!
 set(_BIN_SUFFIX bin sbin)
 if (CMAKE_SYSTEM_PROCESSOR MATCHES "64")
-    LIST(INSERT _BIN_SUFFIX 0 bin64 sbin64)
+    list(INSERT _BIN_SUFFIX 0 bin64 sbin64)
 endif()
 if (WIN32)
     if ("${CMAKE_SIZEOF_VOID_P}" STREQUAL "8")
@@ -262,40 +264,42 @@ else()
         set(_MPI_PREFIX_PATH )
         messagev("Trying to find ${MPI}-MPI implementation")
         if (MPI STREQUAL mpich)
-            #LIST(APPEND _MPI_PREFIX_PATH /usr/lib/mpich /usr/lib64/mpich /usr/local/lib/mpich /usr/local/lib64/mpich)
-            LIST(APPEND _MPI_PREFIX_PATH mpich)
+            #list(APPEND _MPI_PREFIX_PATH /usr/lib/mpich /usr/lib64/mpich /usr/local/lib/mpich /usr/local/lib64/mpich)
+            list(APPEND _MPI_PREFIX_PATH mpich)
             if(WIN32)
-                LIST(APPEND _MPI_PREFIX_PATH "${PROGRAM_FILES_PATH}/MPICH" "${PROGRAM_FILES_PATH}/mpich")
+                list(APPEND _MPI_PREFIX_PATH "${PROGRAM_FILES_PATH}/MPICH" "${PROGRAM_FILES_PATH}/mpich")
             endif()
         elseif(MPI STREQUAL mpich2)
-            #LIST(APPEND _MPI_PREFIX_PATH /usr/lib/mpich2 /usr/lib64/mpich2 /usr/local/lib/mpich2 /usr/local/lib64/mpich2)
-            LIST(APPEND _MPI_PREFIX_PATH mpich2)
+            #list(APPEND _MPI_PREFIX_PATH /usr/lib/mpich2 /usr/lib64/mpich2 /usr/local/lib/mpich2 /usr/local/lib64/mpich2)
+            list(APPEND _MPI_PREFIX_PATH mpich2)
             if(WIN32)
-                LIST(APPEND _MPI_PREFIX_PATH "${PROGRAM_FILES_PATH}/MPICH2" "${PROGRAM_FILES_PATH}/mpich2"
+                list(APPEND _MPI_PREFIX_PATH "${PROGRAM_FILES_PATH}/MPICH2" "${PROGRAM_FILES_PATH}/mpich2"
                 "C:/MPICH2" "C:/mpich2"
                 "${PROGRAM_FILES_PATH}/MPICH2" "${PROGRAM_FILES_PATH}/mpich2"
                 "D:/MPICH2" "D:/mpich2")
             endif()
         elseif(MPI STREQUAL intel)
-            LIST(APPEND _MPI_PREFIX_PATH /opt/intel/impi_latest /opt/intel/compilers_and_libraries/linux/mpi)
+            list(APPEND _MPI_PREFIX_PATH /opt/intel/impi_latest /opt/intel/compilers_and_libraries/linux/mpi)
         elseif(MPI STREQUAL openmpi)
-            #LIST(APPEND _MPI_PREFIX_PATH /usr/lib64/compat-openmpi /usr/lib/compat-openmpi
+            #list(APPEND _MPI_PREFIX_PATH /usr/lib64/compat-openmpi /usr/lib/compat-openmpi
             #    /usr/lib64/openmpi /usr/lib/openmpi
             #    /usr/local/openmpi /usr/local/lib/openmpi)
-            LIST(APPEND _MPI_PREFIX_PATH compat-openmpi openmpi)
+            list(APPEND _MPI_PREFIX_PATH compat-openmpi openmpi)
         elseif(MPI STREQUAL msmpi)
             list(APPEND _MPI_PREFIX_PATH "${PROGRAM_FILES_PATH}/Microsoft SDKs/MPI")
+        elseif (MPI STREQUAL mpistub)
+            list(APPEND _MPI_PREFIX_PATH mpistub)
         elseif(MPI STREQUAL mvapich2)
-            LIST(APPEND _MPI_PREFIX_PATH mvapich2 mvapich)
+            list(APPEND _MPI_PREFIX_PATH mvapich2 mvapich)
         elseif(MPI STREQUAL poe)
-            LIST(APPEND _MPI_PREFIX_PATH /usr/lpp/ppe.poe)
+            list(APPEND _MPI_PREFIX_PATH /usr/lpp/ppe.poe)
         elseif(MPI STREQUAL cray)
-            LIST(APPEND _MPI_PREFIX_PATH /opt/cray/mpt/4.1.1/xt/seastar/mpich2-gnu)
+            list(APPEND _MPI_PREFIX_PATH /opt/cray/mpt/4.1.1/xt/seastar/mpich2-gnu)
         elseif(MPI STREQUAL MPI_TYPE_UNKNOWN)
             message(WARNING "MPI implementation unknown. Compilation process has not been tested/verified yet")
         else()
             message(FATAL_ERROR "Unknown MPI value '${MPI}'. Your options:
-1. Use one of 'mpich','mpich2','openmpi','intel','mvapich2' or 'msmpi'
+1. Use one of 'mpich','mpich2','openmpi','intel','mvapich2', 'mpistub' or 'msmpi'
 2. Do not define the MPI variable and let CMake find the system default")
         endif()
     else()
@@ -367,7 +371,10 @@ set(_MNEMONICS
     openmpi
     intel
     mvapich2
-    msmpi)
+    msmpi
+    mpistub
+)
+list(LENGTH _MNEMONICS _MNEMONICS_COUNT)
 # If the detection fails, this value is returned.
 set(MPI_TYPE_UNKNOWN unknown)
 # Patterns to match the include and library paths - must be in same order as _MNEMONICS
@@ -378,6 +385,7 @@ set(_PATTERNS
     ".*(intel|impi)[/|-].*"
     ".*mvapich(2)?([/|-].*|$)"
     ".*microsoft(.*|$)"
+    ".*mpistub(.*|$)"
 )
 
 ############################################################
@@ -510,7 +518,6 @@ function (interrogate_mpi_compiler lang try_libs)
         set(MSMPI_ARCH_DIR x86)
         set(MSMPI_ARCH_DIR2 i386)
     endif()
-
     # If MPI is set already in the cache, don't bother with interrogating the compiler.
     messagev("interrogate: ${interrogate}, inc path:${MPI_${lang}_INCLUDE_PATH}")
     messagev("libs: ${MPI_${lang}_LIBRARIES}")
@@ -913,7 +920,10 @@ function(unset_mpi lang)
     set(MPI_${lang}_LIBRARIES "MPI_${lang}_LIBRARIES-NOTFOUND" CACHE STRING "Cleared" FORCE)
     set(MPI_${lang}_COMPILER "MPI_${lang}_COMPILER-NOTFOUND" CACHE FILEPATH "Cleared" FORCE)
     set(MPI_${lang}_LINK_FLAGS "" CACHE STRING "Cleared" FORCE)
-    set(MPI_EXTRA_LIBRARY "" CACHE STRING "Extra MPI libraries to link against" FORCE)
+    if (lang IN_LIST "C;CXX")
+        set(MPI_LIBRARY "" CACHE STRING "MPI library to link against" FORCE)
+        set(MPI_EXTRA_LIBRARY "" CACHE STRING "Extra MPI libraries to link against" FORCE)
+    endif ()
     unset(MPIEXEC CACHE)
     unset(MPI_${lang}_FOUND)
 endfunction()
@@ -932,7 +942,8 @@ function(check_mpi_type lang)
             return()
         endif()
     endif()
-    foreach(IDX RANGE 5)
+    math(EXPR _MNEMONICS_RANGE_LIMIT "${_MNEMONICS_COUNT}-1")
+    foreach(IDX RANGE ${_MNEMONICS_RANGE_LIMIT})
         list(GET _MNEMONICS ${IDX} MNEMONIC)
         list(GET _PATTERNS ${IDX} PATTERN)
         messagev("Checking '${INC_PATH} MATCHES ${PATTERN} OR ${LIB_PATH} MATCHES ${PATTERN}'")
@@ -944,6 +955,8 @@ function(check_mpi_type lang)
                 break()
             elseif (MPI STREQUAL MNEMONIC)
                 messagev("MPI set, Detected MPI-${lang} implementation: ${MNEMONIC}")
+                list(APPEND _MPI_DETECTED_MNEMONICS ${MNEMONIC})
+                break()
             endif()
         else()
             messagev("Matching MPI? '${MPI}' == '${MNEMONIC}'")
@@ -952,6 +965,7 @@ function(check_mpi_type lang)
             if (MNEMONIC STREQUAL mpich)
                 set(_PROIR_TO_TEST_VALUE ${CMAKE_REQUIRED_INCLUDES})
                 set(CMAKE_REQUIRED_INCLUDES ${MPI_${lang}_INCLUDE_PATH})
+                unset(MPICH_VERSION_FOUND CACHE)
                 check_symbol_exists(MPICH_VERSION "mpi.h" MPICH_VERSION_FOUND)
                 set(CMAKE_REQUIRED_INCLUDES ${_PROIR_TO_TEST_VALUE})
                 if (MPICH_VERSION_FOUND)
@@ -962,6 +976,7 @@ function(check_mpi_type lang)
             elseif (MNEMONIC STREQUAL openmpi)
                 set(_PROIR_TO_TEST_VALUE ${CMAKE_REQUIRED_INCLUDES})
                 set(CMAKE_REQUIRED_INCLUDES ${MPI_${lang}_INCLUDE_PATH})
+                unset(OMPI_MAJOR_VERSION_FOUND CACHE)
                 check_symbol_exists(OMPI_MAJOR_VERSION "mpi.h" OMPI_MAJOR_VERSION_FOUND)
                 set(CMAKE_REQUIRED_INCLUDES ${_PROIR_TO_TEST_VALUE})
                 if (OMPI_MAJOR_VERSION_FOUND)
@@ -969,6 +984,17 @@ function(check_mpi_type lang)
                     list(APPEND _MPI_DETECTED_MNEMONICS ${MNEMONIC})
                     break()
                 endif ()
+            elseif (MNEMONIC STREQUAL mpistub)
+                set(_PROIR_TO_TEST_VALUE ${CMAKE_REQUIRED_INCLUDES})
+                set(CMAKE_REQUIRED_INCLUDES ${MPI_${lang}_INCLUDE_PATH})
+                unset(MPISTUB_VERSION_FOUND CACHE)
+                check_symbol_exists(MPISTUB_VERSION "mpi.h" MPISTUB_VERSION_FOUND)
+                set(CMAKE_REQUIRED_INCLUDES ${_PROIR_TO_TEST_VALUE})
+                if (MPISTUB_VERSION_FOUND)
+                    messagev("Detected MPI-${lang} implementation: ${MNEMONIC}")
+                    list(APPEND _MPI_DETECTED_MNEMONICS ${MNEMONIC})
+                    break()
+                endif ()
             endif ()
             # Pattern does not match but we have a matching desired MPI type - set to not found!
             if (MPI STREQUAL MNEMONIC)
diff --git a/CMakeScripts/OCDetermineMPI.cmake b/CMakeScripts/OCDetermineMPI.cmake
index 73ac10d..f0877f0 100644
--- a/CMakeScripts/OCDetermineMPI.cmake
+++ b/CMakeScripts/OCDetermineMPI.cmake
@@ -16,13 +16,15 @@
 
 macro(clearFindMPIVariables)
     unset(MPI_FOUND)
+    unset(MPI_EXTRA_LIBRARY CACHE)
     foreach ( _lang C CXX Fortran)
         unset(MPI_${_lang}_FOUND)
-        unset(MPI_${_lang}_COMPILER)
-        unset(MPI_${_lang}_COMPILER_FLAGS)
-        unset(MPI_${_lang}_INCLUDE_PATH)
-        unset(MPI_${_lang}_LINK_FLAGS)
-        unset(MPI_${_lang}_LIBRARIES)
+        unset(MPI_${_lang}_NO_INTERROGATE CACHE)
+        unset(MPI_${_lang}_COMPILER CACHE)
+        unset(MPI_${_lang}_COMPILER_FLAGS CACHE)
+        unset(MPI_${_lang}_INCLUDE_PATH CACHE)
+        unset(MPI_${_lang}_LINK_FLAGS CACHE)
+        unset(MPI_${_lang}_LIBRARIES CACHE)
     endforeach ()
     unset(MPI_Fortran_MODULE_COMPATIBLE)
     unset(MPI_DETECTED)
@@ -31,23 +33,31 @@ macro(clearFindMPIVariables)
     unset(MPIEXEC_PREFLAGS CACHE)
     unset(MPIEXEC_POSTFLAGS CACHE)
     unset(MPIEXEC_MAX_NUMPROCS CACHE)
+    unset(MPI_LIBRARY CACHE)
+    unset(MPI_EXTRA_LIBRARY CACHE)
 endmacro()
 
+# Start from fresh every time?
+clearFindMPIVariables()
+
 unset(SUGGESTED_MPI)
 # MPI_HOME specified - use that and fail if there's no MPI
 # We also infer the MPI mnemonic from the installation at MPI_HOME
 if (DEFINED MPI_HOME AND NOT MPI_HOME STREQUAL "")
     log("Using MPI implementation at MPI_HOME=${MPI_HOME}")
+    log("OPENCMISS_MPI: ${OPENCMISS_MPI}")
     find_package(MPI QUIET)
-    if (NOT MPI_FOUND)
-        log("No MPI implementation found at MPI_HOME. Please check." ERROR)
-    endif()
-    if (NOT DEFINED OPENCMISS_MPI)
-        # MPI_DETECTED is set by FindMPI.cmake to one of the mnemonics or unknown (MPI_TYPE_UNKNOWN in FindMPI.cmake)
+    log("Detected MPI for MPI_HOME is: ${MPI_DETECTED}")
+    if (MPI_FOUND)
         set(OPENCMISS_MPI ${MPI_DETECTED} CACHE STRING "Detected MPI implementation" FORCE)
+    else ()
+        log("No MPI implementation found at MPI_HOME. Please check." ERROR)
     endif()
+    if (MPI_HOME_BUILD_TYPE)
+        set(OPENCMISS_MPI_BUILD_TYPE ${MPI_HOME_BUILD_TYPE})
+    endif ()
     if (NOT DEFINED OPENCMISS_MPI_BUILD_TYPE)
-        set(OPENCMISS_MPI_BUILD_TYPE USER_MPIHOME)
+        set(OPENCMISS_MPI_BUILD_TYPE unknown)
         log("Using MPI via MPI_HOME variable.
 If you want to use different build types for the same MPI implementation, please
 you have to specify OPENCMISS_MPI_BUILD_TYPE. Using '${OPENCMISS_MPI_BUILD_TYPE}'.
@@ -86,7 +96,7 @@ else ()
         if(OPENCMISS_MPI_USE_SYSTEM)
             log("Looking for default system MPI...")
             find_package(MPI QUIET)
-			log("System MPI found: ${MPI_DETECTED}, ${MPI_FOUND}")
+            log("The default system MPI detected is: ${MPI_DETECTED}, is it available? ${MPI_FOUND}")
         endif()
         
         # If there's a system MPI, set MPI to the detected version