I think using a contained hash table as workaround for the bugged private variables wouldn't be too much of a hassle, that doesn't help with the missing width/height actions though.
I don't know if there's any reason at all the object doesn't have these actions. I hope it's not by design to make some of the Light object's functionality possible in the first place. Someone from Scirra or somebody who is currently involved in developing Construct Classic (hey lucid, hey r0j0
) could clarify this issue I suppose.
I'd also very much like to see this resolved and not only because I'm itching to get my hands on Daiz' and Zotged's great looking project.