The Tactics creator seems a little better. Just did two experiment games with Liberos. One behind a lone center back, the other behind two center backs. The Libero generally will sit right on top of the lone center back (in my case Luiz sitting on top of Terry) instead of getting forward, although when the CB drifted to the side for whatever reason he would step in front hesitantly. The game with the 3 defenders, on the heat map at the end of the game Richardo Carvalho's average position was actually higher up the pitch than the two central defenders, so that's very promising.
The solution to getting a libero forward in a 4 back set while keeping one man back to mark the lone #9 IMO seems to be to play with a sweeper, who will keep an eye on the forward, and then give extremely attacking instructions to the CB, although keep him in check with man-marking the #9 on defense. Didn't work in FM11. Hope it works here, but I have some hope.
Also, I think the interface is probably a lot more straight forward for beginners, but I'm having a hell of a time getting to things quickly in this version. So many different tabs when in previous versions everything was on one screen. Just as an example, you used to be able to right click on a player in the formation, and the player instructions would pop up next to the formation. This year you have to go to a separate tab and then pick the player from a drop down menu, which is confusing and unnecessary.