Currently the code results in a bunch of messages similar to the following appearing in the log,
[Client thread/ERROR] [net.blay09.mods.kleeslabs.KleeSlabs]: Slab quartzSlabDarkHalfFull could not be found., and the slabs don't break properly in game.
The block it should be looking for is quartzSlabDarkFull, so Half is being accidentally left in by the regex in the config.
I believe simply replacing (.+)(?:Half)? with (.+)(?:Half) should do the trick!

Edit: Sorry to combine issues, but this one is related and tiny, Botania is not listed in the default config.