Hey, so I added this to Crucial 2, but I have noticed that the textures for slabs are becoming... slightly less reliable. I keep running into an issue where the "missing texture" texture replaces the whole block space, until I remove the slab and replace it. This happens with both vertical and regular horizontal slabs. And it doesn't affect all the slabs in the area... just one... and only every once in a while. I first found this in one horizontal slab, and I changed the design to remove it... but now it's happening in vertical slab... but even tho there's a whole wall of vertical slabs, it's only one that's affected.

Hi there! Apologies for the delay in responding to this, I've had a really hectic year at university and have only just got round to checking the issues. Does this still occur? Also which double slabs version are you using? And lastly if you could provide the debug log file that would be fantastic! Thanks

I retired that world. I kinda ebb and flow with Minecraft, y'know? Anyways, I remember it was one of the stone slabs I was using on the roof of one build, but that's about all. Of course, I don't have a debug log file at this point. Sorry! If that's too vague, feel free to archive this problem!

Old issue, but I'm experiencing the same thing in my world. Installed mod, placed a stone brick slab on top of a dark oak slab, all was well. Saved & quit. When I reloaded the world, it's a missing texture.
Here is my debug log: https://paste.ee/p/vTA0F