I am having a problem with Imagejet for darks paper. When I try and line it up/center it on the shirt it starts to curl up so bad from the heat of the press before I can get it centered right. I have researched the forum and I think what I found is I should use Heat Transfer Mask for Opaque Transfer Papers? Am I correct or is there something I am doing wrong? Thank you so much for any help you can provide. Is there a better paper to use for darks?