Ok, looking back I didn mis-nomer a few. #4 try looking up C. "Fairy Castles"
#2 Try Azureocereus, in strong light it should turn bluish. #7 I think is the plain C. tetragonus.
The splitters have had their way with the Cactacaea, it is ongoing but Dr. Hunt (no relation) of the Cactaceaen Systematics Group is ready to set it straight with the Newest Lexicon since Backeburge in June of this year. Complete with Atlas of habitats. Should be an excellent peice.
The lime you'll probably find in a bright yellow bag with red lettering. (P.S. I also use on my Clematis, they love it.)