Ok, so a few issues here, the last of which game breaking. These are all from my experience while playing with a friend though, and we did move the world from 1.4.1 to 1.4.4:
-In the Nether, there was no base spawned like the 1.4.4 quest said there would be(though flying spiders are the absolute worst)
-Couldn't find the Egyptian coin, but this is because we couldn't update the specific world needed because we ported the save over
The last of which is the most confusing and the worst: We just finished building the Nuclear Fusion Chamber, when I; I didn't see it as complete, I still saw the blueprint overlay, and my inventory was acting wonky. My friend, who finished it while I was working on bees, could see it fine and everything was normal for him(he was the server). I disconnected, reconnected, everything looked fine and my inventory was back. We tested a few chemical combinations just to make sure it worked, the fusion star was in, everything was looking up. Then, after putting a transfer node on the Fusion Chamber, the game crashed, apparently terminally (friend is the one working w/ it, I don't know if a rollback is possible). Even if we're sure that transfer node+fusion chamber is the cause, this is a big problem in compatibility