kello: did you make yours with regular sugar, versus isomalt?
I'm going to post my thread I started when I was trying this out--maybe you can just email the posters who were helping me and ask them.http://cakecentral.com/cake-decorating-ftopic-735165-0-days0-orderasc-isomalt.html
Also, SugarCraft has great info on making isomalt gems and using them. Also, I've read others who have simply melted Jolly Ranchers and used that in molds. I'm not sure what your time line is, but I'm just throwing everything out there that I remember coming across in my search.
And by the way, after two attempts, I didn't even use them! I just moistened the gum paste number and coated it in colored sugar crystals
I needed to make the tiniest jewels in the molds I had, so maybe that made it that much harder to accomplish. Maybe I'll try again next time, but only if I need the larger jewels.