BC Version: 6.1.8
Chisel Version: 2.0.0.3
Chisel Facades Version: 1.7.10-cricket-DEV

In my ChiselFacades mod, I add Chisel's blocks as Facades using the add-facade blockName@metadata IMC.

With BC 6.1.8, the Facades are visible in the creative menu and in NEI, but only the first metadata version of each block's facade can be crafted in the Assembly Table (metadata 0 for Chisel-added blocks like Factory Blocks, metadata 1 for Vanilla-based blocks like Redstone Blocks).

If spawned in through the creative menu or NEI, the Facades render without issue.

This album should help demonstrate the issue.

This issue doesn't occur in BC 6.0.18.

The Chisel and Chisel Facades links above are to deobfuscated builds that can be used to test/reproduce this. You can enable debugging output in the Chisel Facades config file to make it output a list of block names and metadata values it tried to register Facades for to ChiselFacadesDebug.txt in the Minecraft directory.

@Choonster bc also provides ItemStack sended Support. Java sometimes have trouble with Splitting numbers^^" I had that trouble with my Whole World Retrogen (i readed the regionFiles and the were only numbers).
So try it out with Sending ItemStacks instead of Strings (that possebility should exsist) and if it still fails then i think it is a BC bug^^"
Correct me if i am wrong.

Using an ItemStack message instead of a String message doesn't work, unfortunately (the same issue occurs).

Thanks for the suggestion anyway.

@Choonster - do Chisel ItemStacks return true for getHasSubtypes()? If no, that's a bug on your side.

Every block + metadata combination I register a Facade for returns true from getHasSubtypes().

@Choonster - Fixed for BC 6.2.1. It was indeed an issue with IMC, but it took a while to figure out.

Good to know, thanks.