Well, this is what I have suggested as the proper course of action, post-2.6, several times; and nobody even responds to it. :/
Ah, so I'm not the only one that finds Lua to be a bit awful? Really, it's one of the main reasons that I haven't made a Solarus quest--every flipping thing is coded in Lua. You can't do a blasted thing, without coding it as a Lua block, other than place graphics, which are read form a text file listing all of them, into the Lua engine.