I'm having issues with the savedState files in Mac OS X occasionally. For example, one of our client customers experienced a FileMaker Pro crash on just one of their computers, and tried for an hour to reopen FileMaker Pro only to have it immediately crash before even the database choice dialog would appear. It finally did open though I'm not privy to the specific sequence of events they tried to resolve the situation.
I also had three computers (my personal laptop included) that, just the other day, did the same thing after I had installed the new Troi Activator update in the plugins table for that database. (My database automatically checks that table for any updates to plugins and installs them accordingly using the newer container technologies FileMaker implemented to accomplish that.)
The only solution was to delete the folder ~/Library/Saved Application State/com.filemaker.client.pro12.savedState (or com.filemaker.client.advanced12.savedState for mine) which contains the Mac OS X savedState files specific to each application that opens.
There are a couple of 'solutions' that I've found but nothing so simple as a checkbox in a System Preferences panel. One solution was to quit FileMaker, then lock the above mentioned savedState folder. Another one uses the terminal command below, though I am not sure this works in Mountain Lion (my deleted folder still reappeared when I opened FileMaker Pro but the modification times are not changed in later reopenings).
defaults write com.filemaker.client.advanced12.savedState NSQuitAlwaysKeepsWindows -bool false
Any comments or suggestions (especially from FileMaker staff) would be appreciated. This seems to be a real problem and I would be interested to understand much more about the specifics of how FileMaker Pro interacts with Mac OS and the savedState feature at the base level.