The current Solid-only wall should accept fixed-solids, like the old Gas-wall used to.
Even Catelite liked the Gas-wall "bug", from what I read in my Gas-wall thread. :3
Also, none of the previous posts make a single shit of sense and the authors are clearly derpwads who didn't read the main post. Yes, powders ARE solids, but so are SOLIDS themselves. You try drawing a solid ontop of solid-only wall, it's deleted.
@jenn4 It's meant to only allow solids. Right now it only accepts powders, which, yes, are solids, but I mean fixed-solids. It currently does not allow, for example, DMND, which is a solid.