I overlooked this when doing the upgrade from Beta 2 to CTP. I just started the install, loaded the drives in GUI mode when it asked for them, and walked away while it was installing. I forgot about the text mode asking for additional drivers. So, when WHS was done installing, I had to install my RAID controller setup. I was excited to see that WHS kept all the files that were on those hard drives (I thought they would have been removed). However, now I get "file handle invalid" whenever I try to access files from WHS. So I had to wipe WHS clean of all shared files (had to login to WHS machine directly to do this, since I was getting errors when attempting it from a network machine), then I had to put them all back after the upgrade.
Moral of the story... Wait for text mode of the install and load the additional drivers.