Poking around the module, it looks like it is in, but not properly linked with the AT.
There are three areas labelled Arcane Tower Interiors with tags: PH_0001ar, PH_0002ar and PH_0003ar.
PH_0002ar appears to be the "main" level.
There are several other Arcane Alliance areas from the old design in there. They can all be removed, I think.
I tried placing a furniture deed in all three of theseareas but it didn't work.
I'm not familiar with what this tower was supposed to be internally, but I'm guessing it's the PH_0002ar area that was supposed to be linked up with the housing system.
Oh...and the front door to the tower doesn't seem to be closing itself either.