I have been adding to my sky box build. I added a second room and a swimming pool.
There are a number of phantom prims in this build. The curtains are phantom so you can walk through them. I made the main section of pool water phantom so when you walk into the pool you actually are *in* the water. I needed a non-phantom prim underneath the water so people don't fall to the ground 650 meters below.
So I built and fussed with placement and then decided to link everything up. When I clicked link I suddenly found myself free falling. Why? When you link phantom to non phantom prims the entire build becomes phantom, which I may have known or may have forgotten. In any case, I was falling to the ground.
It took me a few attempts but I somehow managed to link up the phantom prims with the regular prims, which builders who know more than me say should not be possible. Please don't tell Linden Lab, ok?
(I know, I know. I should have taken the pareo off before I went in the water.)