If you want to deploy your application to be able to use both 32-bit and 64-bit .NET, you need to build liblmxnet.dll with the 32-bit and 64-bit .NET compiler. Note that both copies of these files this file should be shipped with your application.
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Compile the LM-X SDK as usual for x64:
Panel C:\Program Files\X-Formation\LM-X SDK v4.8.4 win64_x64>(configure your environment for 64-bit compilation)
C:\Program Files\X-Formation\LM-X SDK v4.8.4 win64_x64>nmakeCopy the generated C:\Program Files\X-Formation\LM-X SDK v4.8.4 win64_x64\win64_x64\x-formation_pair.snk to the equivalent directory of the 32-bit SDK:
Panel C:\Program Files (x86\X-Formation\LM-X SDK v4.8.4 win32_x86\win32_x86\x-formation_pair.snk
Proceed with compiling the LM-X SDK for x86:
Panel C:\Program Files (x86\X-Formation\LM-X SDK v4.8.4 win32_x86>(configure your environment for 32-bit compilation)
C:\Program Files (x86\X-Formation\LM-X SDK v4.8.4 win32_x86>nmake