PipelineTool.exe (on windows) should be x86 not AnyCpu.
MGCB.exe (on windows) should have been x64 not AnyCpu.
General rule is: executables target a particular architecture, dlls target AnyCpu.
If you leave your executable as AnyCpu then its performance (like it crashing on startup) can vary depending on the machine you run it on, which just makes everything more complicated.