I'm making a cake topper that will be fairly thin and fragile. I'm wondering what would be the best medium to make it out of: gumpaste, white chocolate or royal icing?
The humidity has been high here recently and last weekend my topper (a gumpaste rainbow) left the house solid as a rock and when I arrived at the party and went to pick up the topper it was so soft I couldn't even pick it up!
I am planning on airbrushing or luster dusting the colour on after it is done.
I could really use some advice on this one, thanks!

White chocolate is affected by heat but not humidity...but it breaks easily and is harder to airbrush when you are done, the color may bead up on it a bit.

Royal is also brittle and can melt faster than gumpaste in water.

I would vote gumpaste all around....just make sure it dries completely (like at least a full week) before using it, and then box it up carefully and bring it to the venue if you have a problem with it melting.

I've never had gumpaste melt on me before but maybe its not as humid here? I dunno.

Gumpaste has my vote. I have issues with humidity (ugh) and I have never had any problem with gumpaste melting or even getting soft once it's dried.

Lots of people use pastiallage in high humidity. If you don,t have that, then gumpaste.

Thanks! I did opt for gumpaste - so far so good! I'll let you know how I make out.
Thanks again!
K