I have a problem, switching to another process from spring while a game is in progress freezes my system until I switch back to spring when it resumes. I am using NVIDIA

I have also tried the config value FixAltTab = 1, no go

I have tried to suspend spring.exe before switching and then resuming but then spring becomes unusable

I reported it to mantis and it is probably a gfx driver issue. However, it is strange that both ATI and NVIDIA can be affected. Did you try different drivers, including older ones?