KiwiHawk says they decided to remove stone from the undergrounds recipe if Cerys is installed (and also to let belts freeze).
The missing piece is glass, but we can insert a patch in Cerys for this. I would be grateful if Bob’s players can suggest an appropriate item&percentage for scrap recycling.
Seeing as how its only really needed for the base level chem plant, a very low percentage (& number) is really all that's required to get initial chem plants up and running. Basically by the time you probably need to build higher level chem plants that are available in Bob's Assemblers mod, you can probably drop them from orbit.
You could even make it so if Bob mods are installed, Glass is salvaged from the ruins that lie around Cerys. Enough to build say like 50~ Chemical Plants. This is probably a gross oversupply, but its supply nevertheless.
The funny thing is, due to the random selection of nuclear junk that drops from the nuclear scrap, a lot of bob materials are natural available on the Planet anyway. Turbines for example require Cobalt from the mod, however Turbines drop freely on Cerys so Cobalt is readily available in large quantities.
There is a very odd compatibility issue I have noticed where Bob's Centrifuge 2 and 3 (upgrades to the normal centrifuge, which are easy to craft on the planet) cannot re-process the spent nuclear fuel from the reactor, however the base Centrifuge can.
I also noticed another issue where the magnetic particles were not changing the uranium 238 on belts into Plutonium (cerys) the particles would impact the uranium but nothing would change. I wasn't able to pinpoint what mod was causing this issue but I have suspicions it was either A. Bob (since it has its own plutonium) or B. Shattered Planet, which also adds its own Plutonium. It worked initially with Shattered Planet installed, however after an update, it didn't work anymore, so I have my suspicions it might be the cause.