i'm trying to suspend shapes in the air simular to this: http://cakecentral.com/modules.php?name=gallery&file=displayimage&pid=1416723
my fondant wouldn't set so I mixed fandant with gumpaste and I got a really great workable product. but now my problem is that i can't get the wires to work. they are sturdy enough but they won't stay. i tried inserting them in the middle but when they were stood up the shapes would slide right down the wire. I tried heating the wire and pushing them into the back but when dried and stood up they would just fall off after a few minutes. it tried pushing the wire in the back and molding the fondant around adn again would just slide down. what am I doing wrong? is there an easier/ better way to do this? please help ASAP!!! THANKS!!!!

Make sure you have a heavy enough wire, and that your pieces are not too thick (which means they won't be as heavy) and then put a dab of gum glue on the wire before inserting - let them dry flat before inserting the COVERED wire into the cake (dip the wire in candy melts or stick them in a coffee stiring straw before putting them in the cake)

You can use fondant to make it too, take a small amount of fondant (about 1/4 t.) and put it in a container with about a teaspoon of water. (If you have gumpaste it is better - or you can use gumtex, tylose etc.) Fondant will work though. It will melt together and you will have glue.

Stars like that are usually made ahead and layed flat to dry on the wire.
Are you pressed for time?
You can heat the tip of your wire with a lighter and then insert it into the fondant/gumpaste and it will heat up and fuse the sugar to the wire. But if the fondant is too soft it will sag and still lose it's shape even if the center is fused onto the wire. Gumpaste would work better. If you are using light colors it will show but dark colors will hide it.

Edit to add. this is NOT FOOD SAFE. Take extra care to be sure no one will try to eat them. And be sure to insert your wires into coffee stirs or straws that you will then insert into the cake-keeping the wire from coming in contact with any cake. Most bendable wires contain lead. (learned this in here thanks to the many wonderful and caring CCer's)