Actually there is no really critical bugs at the moment. In stable branch for sure. At beta (beta branch of alpha test btw! We should keep it in mind) I just started new game and nothing happens with an ice biomes after tenfolds of cycles. Correct temperature of abyssalite surrounding biomes perfectly protect it from melting. Insulated abyssalite tiles works same as usual abys.tiles from previous versions of a game. Drip cooling also fixed. Radiant pipes at the process of fixing and it's ok for new features. All the aforementioned issues are actual for old maps which was built in old circumstances base on old mechanics. The new one works fine, just try to start brand new base and taste it by yourself. At least check out this topic, i'v got similar results and just a littlebit more troubles with insulating than before.