1) it's a wiki. click the "info" link and you'll be taken to a page where you can see (and download) all of the revisions that have been made to the code (here:
http://www.overcards.com/wiki/moin.c...s?action=info)
2) the latest versions need the latest version of autohotkey to run. at the top of each new version of iWitness, the required version of autohotkey is listed.