Is it safe to install or does it introduce new bugs and I should stick with 1.4.2?

I haven't had any problems :)

It's the best version so far. Restarted a new playthrough (never finished the game, only did first 10-13 levels) with this version and NPC animations are far more fluid and the world itself. The performance has greatly improved, there's less delay of AI responses and so on. This could have been the version that Warhorse was pretending to release if they had 2 more months. It will get better, they are honest people that deserve respect for their courage, and will learn from mistakes.

Only found a bug in the first Theresa's quest (first step), when the last dialogue gets repeated and the game crash. Just load your latest save (not the one created after starting Theresa quest) and it will work correctly the second time.