After a little trial and error I have positively identified the culprit: Really Advanced Setup mod. HOWEVER, it only crashes the game if I am using EUI. And, bizarrely, only when I hover over or click the science beaker in the upper left-hand corner. If I do not click the beaker and merely select my research from the prompt above the mini-map, no crash. There might be other odd conflicts, but so far I have not gone far enough into a game to witness them.
Very peculiar.
If you have logging enabled, make it crash that way and then post your lua.log.
G