What am I doing wrong? (LS)

[Vandalin]

http://www.vandalin.net/wanderrest.pdf

This is a pdf of my latest Lair design. I re-worked it in an attempt to make it less likely to need major changes further down the road if things are added...last design had a lot of "one-ways".

For some reason though, the Lair designer in game will not allow me to put the T2 Lair where I want it. It tells me that "Planned structure (Lair T2 Helian Chamber - Lair) has no available expansion openings to attach to. Removing the structure." But if you look at the design it should fit and be attached properly.

Please help! I'm going nuts here (as anyone who was on a little bit ago could attest to).

Thanks!

*edit* For clarification: Problem is on Floor 1.