Thanks everyone! I will try it again and see if refrigerating it helps! After I crumb coated, I put it in the freezer to set up while I worked on my smash cake. There might have been too much condensation as well. Then I decorated and left it in the shade on my counter. My house was a cool 70 degrees all night and day, but perhaps my client's car was too warm. :( Is there a possibility it was my BC? I'll try it again on a family member with a different icing and try the fridge instead!
@ddaigle: I was asleep! ;)
@Nannycook, there is a little button under "Source" in this reply box. It looks like a little picture of a house. Click on that to add a pic.