Yes and it's already lost to the sands of time, which is another reason to not go the independent route. If somebody built off the TDM base, there's a better chance it will get picked up and continued if one person can't do it alone.
As for the transparency point, that's exactly how Thievery works, and it works great. You should watch some videos of it in action (I put part one of a series below). It's fun.
You can see other things they had to do too, like flashbombs whiting out guard's screen, footprints sticking out a bit more, uh, a few other things.
As for the second point, for the game just to work, it's okay for the animations to be kind of basic, just the minimum to signal what the player is doing.. Possibly the basics already there might be fine. Thief2 also has super basic player animations, but it doesn't really matter to enjoy the multiplayer experience, since the other players can still do all the normal thief things. And if it works, you can expect people will improve the animations over time, so it can get released & people can start playing with it well before you've got perfect animations. In my understanding, the biggest task isn't animations but having player events shared across multiple clients for literally every system. But even for that, I think once you've done it for one system, it will be easier to do for the others.