I'm getting the file size from Window's 'properties' menu. I do know that if I open the properties box for 'track01.iso' and don't close it, then replace track01.iso with a different same-named file, Window's will just bring up the old 'properties' box for the new 'track01.iso' (which will have the incorrect size). I'm usually really careful to make sure that doesn't happen. Plus, I use the database to scan and auto-name every ISO I submit- just to verify that the information I submitted matches my actual image.
During the time when redump's site was down for awhile, I couldn't submit dumps or download the updated database so I was recording the info on a text doc. I guess I made some bad mistake in copy/paste and never caught it because I couldn't get the updated database for awhile.
Would it be a good idea to make the PS2 DVD submission form accept the SIZE/CRC/MD5/etc info in CLRMAME dat format (like it does for CDs)? It might eliminate some stupid human errors (like mine) made by copy/paste-ing each field separately.