I should be in bed but I had to share my frustration. I wanted to make a gumpaste shoe for the first time, however it broke in parts before I could complete it. I now see that it was not totally dry. I cut the sole on Sunday and I though by today it would be fine. Now I know it takes more than a few days for gumpaste to dry.
So sorry to hear that. I hope you have time to remake it before your cake is due.
I had the same nightmare a few weeks ago, I turned my broken shoe into a sandal in the end, it still looked good x
Nicholas Lodge's gumpaste dries faster than others that I've tried. I've never had anything take longer than two days to dry with it.
If you're ever in a real pinch, you can superglue the broken pieces of gumpaste back together. Just make sure no one eats it which they're not likely to do to a gumpaste shoe anyhow.