I'll try to work on this tonight. Don't have time right now, but one quick thing about the autocropping. The script would
auto-detect the margins and remove them, so it doesn't matter whether they change. (In fact, I've already written a script to do that--
see here, post #9; the mac instructions would be the same as the linux ones.) However, it would crop it down to the smallest possible rectangle without losing anything on the page; meaning that it wouldn't cut out headers and footers if you wanted to cut out headers and footers.