I've made a small donation through 2Checkout, I think PhpDig is great (and IIS is crap). I have it installed over a few other sites (running Apache on Linux) and never had any problems... except on IIS, as with most php scripts out there.
I have phpdig over there:
http://www.emusicmag.com
http://www.soundfontdepot.com
http://www.mididepot.com
and should soon be there:
http://www.homemusician.net
keep up the good work