RE: Monokote?
Just bought a new iron with an accurate temp control. Around 220 degrees it only glues down. No pulling, shrinking, or puckering. The shrinkage chart is accurate. Either you didn't glue down the edges enough, and/or you are too hot. It doesn't ever pull unless you are either really hot, or you didn't glue it down properly....at least with all of the Ultracote I've been buying.
edit: this is only to correct a comment made about Ultracote, not as a criticism about Monokote.