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GalCiv3 Forums
In a game (that I started in 5.2 - not sure if this would make any diff.) when I click to open the diplomacy screen, shortly afterwards the game crashes out on me. I can provide the savegame and any necessary crash logs if required.
I would suggest starting new game fresh with any new patch/update. Any older games/saves may have issues.. 
all part of the beta process.
Please start a support ticket so we can look into this.
Link to support tool:
http://sd.stardock.com/Support/supportToolTest/SDSupportTool.exe
Here is the location for dmp files:
"C:\ProgramData\Stardock\Galactic Civilizations III"
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