Closed-source creations are better off in the 'Your creations' forum. If a developer doesn't want to tell people how they achieved an effect, I don't see a problem with that - but I don't think they should complain if people try to reproduce the effect and post their .caps for it. After all, someone could do the same once you've released it as a full game - or, if you're that worried about whether or not you're the first to use the effect, don't post the effect at all until release!
Letting this one go for now, but please keep Uploads forum open-source .cap files.