Thanks to some idiot(s) that persistently posted links to unacceptable websites (actually, spam-like posting of links of any kind is prohibited everywhere on this site) as comments on the first saguaro picture in the Arizona 2002 album, I have turned off comments for “guests” in the photo gallery. You should be able to post comments by registering, although I haven’t tested that option, and no one has ever requested a registration in the several years I’ve used Coppermine to display my photo collection.
You can still rate photos (although no one has done that yet, either, since I had to reset them after a major glitch in a software “upgrade”).
If later versions of CPG include adequate anti-spam features, I will probably turn comments back on again, although I haven’t seen any useful ones in the five months they were permitted.