This is not specific to GLAT. If you read around on these forums you will see similar complaints with all sorts of teams and these complaints go back years. There is no specific bug, the buttons just disappear when the battle crashes. This has always been a problem with the game but it has gotten significantly worse lately as they continue to add new characters and conflicting status effects that require more complex computations. I think the problems are just baked into the game now and aren't going away. I can't tell you how many GAC's I have lost because my only good counter left crashed.