The below does not guarantee you will get a working Gungame server but it has worked great for us and thought I should share the info.
Using the following versions - I've had a stable server for several hours on Windows Server 2008 R2 with no map change crashes or other random crashes.
GunGame 5.1.477
Eventscripts 2.1.1.338
Metamod Source 1.9.0 hg723
SourceMod 1.4.0 hg3079
sp_extensions_ep2 1.5.0f r78
Loading Gungame is done via autoexec.cfg
Good luck all
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