Hmm, I don't know if I've run into this problem before, but it sure is an interesting one. I will fire up my version and see about replicating it.
Does it really randomly pick either an object/character/inventory object, or is it really just one of these? Well, actually, I guess I could see how it is making a mistake pointing to a specific sprite in the sprite manager. What happens when you hover over the "broken" verb? Does it point to the correct highlighted verb, or to a different sprite, which it thinks is the highlighted version of the correct verb? This could be the point of the bug. Anyways, again, I'll take a look.
Does it really randomly pick either an object/character/inventory object, or is it really just one of these? Well, actually, I guess I could see how it is making a mistake pointing to a specific sprite in the sprite manager. What happens when you hover over the "broken" verb? Does it point to the correct highlighted verb, or to a different sprite, which it thinks is the highlighted version of the correct verb? This could be the point of the bug. Anyways, again, I'll take a look.