FileMaker GO 12 = production software
iOS 6 = developer beta software
Chances are "really good" that FM GO will be updated to run on iOS 6 when it is released (or shortly thereafter). :)
Go 12 hasn't been updated in two months and perhaps they are waiting for the FINAL shipping version of IOS 6 before shipping an update...
Nice to know that someone else has problems with BETA software, especially OS software. :)
However, the current shipping version of Go seems to crash a bit with IOS 5 on my Touch 4... OK, sometimes it might be my fault...