People, please.. <img src="smileys/smiley31.gif" border="0" align="middle" /> <img src="smileys/smiley31.gif" border="0" align="middle" />
Do remember that not all of us are English native, (or even those who are, would be capable to read/write proper English, but that's totally different subject ) so there's plenty of room for misunderstanding.
For the 'hollow mask' .. one has to first want to play the game long enough to see even one drop. Luckily it's the first one (only kind?) so it does appear on decent time. I kinda like the way the visual effect works...
Occasionally it could indeed to be nice to be able to detect selected object hitting some cloud like visual effect with out any designer inserted extra hidden support sprites.
But I do see the point of not making it so. This kind of cloud can be made of thousands of particles and the huge amount of collision checks would kill the entire system performance even when those collisions weren't really needed.
So (as a coder).. I'd recommend not to trust any neat undocumented features or side effects that's not explicitly mentioned on manuals (or developers) since this program is still on development and things can and will change over time..