Minecraft v1.14.4
Forge v28.1.90
Engineer's Decor v1.0.16-b5

Machine blocks, slabs, & concrete slices all drop when broken in creative.

Is that intended for slabs and concrete slices though?

No, but they are made with the same custom drops because they drop different dependent on the block state. I have implemented the config option, first test seem to be okay, so I can very likely push a new version after a general test this weekend. Cheers again for filing this matter.

Hi, this is (better said was initially) intended to allow relocating the blocks with contents and settings. But it's not standard, so I will very likely make a conf option for that.

Is the issue resolved from your perspective?

Yes, thanks!