anthof,
Yes, the windex method and trim solvent are similar in the fact that they activate the adhesive on the back of the monokote. I don't use trim solvent when doing the covering. I put on patterns and trim pieces by using the windex method, then after it has dried and set I go over the edges of the pattern with a trim iron (or a covering iron turned down a little) to seal down the edges. This has worked really well for me.

Here are some pictures of covering I've applied using the windex method and sealing the edges.

Hope this helps.

Ken