mine is 15.6 for sure. the freeze only occurs in enemy turn. so i doubt AI getting internal stacking error which triggers some kind of overflow. same looking bug has been seen in the past, and almost always was there especially in early version. (i.e. Master of Magic, original X-com and Jagged Allience 2)
it seems i have been through demo version now as i can handle any situation without difficulties. what i said about "fixed order is not good" is, even taken one squad team as a unit, there should be some arrange of order within. i mean, its not always Soldier A to B thing (even if it depends on speed/agility value of each.). Soldier A could wait to strike out for best effort with B. that's why serious Turn Based Strategy has "passing/waiting turn/phase/round" function to adapt. i felt this missing badly after i got shotgunner and grenadier in my team. since the set of heavy fire's backing with assault is usually becoming mean punch to stronger enemies.
this part is the very core of tactical scaled strategy. actually its smallest but important part of chain of command and the source of deeper thought and fun for the player.
i think pre-made personality is good. it adds atmosphere and natural feeling to game's progression. but please don't become too restricted to fit only to those pre-made characters. it kills not only longevity but replayability since it becomes boring flashback once the player got through. (it's like splash/intro movie of computer game.)