Pat's right about Painter scripts and custom brushes. Not only that, but all libraries have to be the same when the script is played back. Otherwise, the script will come to a halt.
In any case, Painter scripts are iffy and I've had the best luck when recording only small scripts and playing them back in the same Painter session or shortly after when I still have things set up the same way.
Please do not PM me with Painter questions. Instead, post them here where everyone can benefit from them. Thanks!