This scenery is beautiful and easy on frame rates. For those of you with ai problems, I found two things wrong in my setup.
One, I had a rogue FS9 ai file in a different folder than the usual scenery/global/scenery folder. Letting AI Flightplanner search my entire FSX disk found it in a scenery folder outside FSX.
Once that rogue file was found, my ai showed up as full shadows and canopies. That's all that would show. This was the package ai, all my others were working fine. I have 6GB RAM, AMD Phenom II 810 Quad core running at 2.6GHz, with an ATI FSX 4800 series with 1GB RAM. Running WIN 7 Home Premium. Everything was working fine, except the way the package ai was showing. MY resource meter showed I had slightly less than 1GB of unassigned RAM left. So I rebooted, and everything works fine. Seems I have a memory leak somewhere. I realize this is a very rare cause, but if it helps anyone, it's worth posting.
This scenery is awesome, and itself is NOT the cause of any problems on my rig.