ehm, i have encounterd a Problem multiple times, that is not 100% crashing (it only crashes the "overlay" where you chose your buildings. spells, missions etc.)
So far, that only happens to me, when i had rallyd my troops (i play slowly and horde a lot of troops before i attack) and use the heal-Spell on them, when there for exampel attacking a Door, so when there stact a lot. The Game will continue to play and i can finish lvls with using hotkeys, but i cant click anything on the buildingtab or see the "ESC"-Screen. Everything besides the Gamepart where the action happens is stuck forever at just the second i clickt the heal upon the stack.
oh, and i doubt that its my PC, i use a on-top gaming PC + i play it as an Steam-game(up to date / i don´t know if you can play it somwhere else^^)