These parts are not in the current pack, unfortunately! It is one of the oldest packs from Screaming Brain Studios, so I am actually working on a revamped/updated version of the entire pack, that should come out sometime this year! It will contain floors, ceilings, and backgrounds matching the style of those in the article, as well as an updated version of the tutorial related to how to create these types of floors and ceiling tiles yourself! I apologize for any confusion!
Since the time of the new package is uncertain, can you put various types of raw material into the package? I can complete the missing parts according to the article
I could probably update this one as I get parts done! I've got a few new pieces for the floors and ceilings, though not enough to cover all the materials in the current pack. Hopefully, I can knock out the update sooner rather than later!