Attempting a swimming pool cake.  Will piping gel melt gumpaste/fondant 60/40 figures?  Thanks for your help!

If I remember right yes, it will.  Can you add the figures at the very last minute? 

One of the first decorated cakes that I did was a swimming pool birthday cake for my husband.  My figures were made of gum paste and the piping gel did not melt them at all.

I had had no problem.  Piping gel with fondant figures made several hours ahead. 

I also had no problem with melting.