Devlev, you're amazing. This VBS script is beautiful with the thoughtful auto popup dialogs and everything. The only thing I changed was removing the opening of the Explorer window, since it doesn't seem to open the music directory anyway.
I did some testing and now I've added the following formatting as a custom tag to my regular formatting action to store the original date modified timestamps for my collection:
$if2(%last_file_mod_datetime%,%_file_mod_datetime%)
This essentially solves the problems of ReplayGain thread I posted! Now I can apply RG in foobar2000 and then restore the original timestamp using Mp3Tag. Perfect. Thanks so much 