With the DG skins, just spend a little time rubbing the edges down well. Once they're adhered properly, there's no more peeling. I tried to put my bumper on with 30 minutes of application--and without really smoothing those edges--and I had the same problem you did. Once I took a couple of minutes to really press it all down, and then let it sit for an hour or so, I never had another problem with them. Pulled the bumper off today to try and clean a scuff mark off of it, and then skin stayed put perfectly even when I put the bumper back on.
Couldn't get the black mark off my pink bumper though, which is disappointing. (Tried a Mr. Clean Magic Eraser--I'll probably try something else.) The non black ones are going to be a pain to keep clean, I'm thinking.