I started with this mod, and ignored the recommendation of using it on the first autosave. I did it on a pre-existing save more than have way through Act 1. The game did crash a couple times, it doesn't like your first boat ride (my 5th party member had issues -- so I kicked them out of the party before the boat and added them back in after), and it always complains when it loads about the save being corrupt or tampered with and highly recommends you don't continue with it, but other than that it has been working great. I've only been running with 5 (my main and the 4 companions I ran across) so it might be different with 6.
The inventory and character panels scroll left/right even though there is plenty of screen space, but a minor inconvenience that will hopefully get fixed down the road. I play on a 5120x1440 ultra-wide screen, so the UI only using the center 50% of my screen isn't great.