Hello :)  I have been away from cake decorating for several years and I am just now getting back into it.  I have a cake that I will be working on in a couple of weeks that normally I would use color flow and color in the character that I would be using...but with this cake, the character will be used as a topper.  And, if I remember correct, the Crisco used in my buttercream will break down the color flow.  So, I began wondering if  the candy melts could be used to color and make the topper?  If not, does anyone have any suggestions as to how to place the topper so as not to come into contact with the buttercream?

You can pipe candy melts to make the topper.  If the topper is going to lie flat on the buttercream and you want to use color flow, you can brush the back of it with piping gel, or insert sugar cubes into the icing and attach the topper to them with some royal icing or more color flow.  That keeps the back of the topper from touching the BC directly.

I like Maybenot advise,

also, a thin cake board underneath the topper? It would just need lifting when ready to cut. Ive used candy melts successfully . Not sure if this would work not knowing your design 

Thank you!