I understand that this is a work in progress, and not really ready for release at this point. I tried to play, and watched the video after ending in unwinnable states a couple of times.
I'll try to come with some constructive advice. That may be silly, because I don't know how SCUNK works, but at least in AGS, some of your issues are easily fixed. In AGS too, a character may be present in a room where the player is not, but dialogue is not limited to that room. There is a character.sayat - command that can be used even if the fly is not in the room. If that is not the case here, then surely there must be a display command or something that can show the sound effects?
Do not hide jokes. I didn't try the same MI-line several times on the spider because it was the same line. If you want the player to keep talking, swap the dialogue option with a new one.