I tried to play STL on FSO 22.2 and MVPs 4.6.6, and through the first three missions I had no problem.
However, when I tried to play the fourth mission I got this error:
Error: Can't open model file <Fenris.pof>
File: modelread.cpp
Line: 1406
ntdll.dll! NtWaitForSingleObject + 20 bytes
KERNELBASE.dll! WaitForSingleObjectEx + 142 bytes
fs2_open_22_2_0_x64_SSE2.exe! <no symbol>
fs2_open_22_2_0_x64_SSE2.exe! <no symbol>
fs2_open_22_2_0_x64_SSE2.exe! <no symbol>
fs2_open_22_2_0_x64_SSE2.exe! <no symbol>
fs2_open_22_2_0_x64_SSE2.exe! <no symbol>
fs2_open_22_2_0_x64_SSE2.exe! <no symbol>
fs2_open_22_2_0_x64_SSE2.exe! <no symbol>
fs2_open_22_2_0_x64_SSE2.exe! <no symbol>
fs2_open_22_2_0_x64_SSE2.exe! <no symbol>
fs2_open_22_2_0_x64_SSE2.exe! <no symbol>
fs2_open_22_2_0_x64_SSE2.exe! <no symbol>
fs2_open_22_2_0_x64_SSE2.exe! <no symbol>
fs2_open_22_2_0_x64_SSE2.exe! <no symbol>
fs2_open_22_2_0_x64_SSE2.exe! <no symbol>
fs2_open_22_2_0_x64_SSE2.exe! <no symbol>
fs2_open_22_2_0_x64_SSE2.exe! <no symbol>
fs2_open_22_2_0_x64_SSE2.exe! <no symbol>
fs2_open_22_2_0_x64_SSE2.exe! <no symbol>
fs2_open_22_2_0_x64_SSE2.exe! <no symbol>
fs2_open_22_2_0_x64_SSE2.exe! <no symbol>
fs2_open_22_2_0_x64_SSE2.exe! <no symbol>
fs2_open_22_2_0_x64_SSE2.exe! <no symbol>
KERNEL32.DLL! BaseThreadInitThunk + 20 bytes
ntdll.dll! RtlUserThreadStart + 33 bytes