Tim: This took me forever to work since all the forums don't actually address this. Like you, I only wanted to delete a couple of photos off my phone from my picasa account, not the whole picasa album.
You were on the right track by going to Google+ on your PC and deleting the individual photos from there. Next, go back to your phone and go to the home screen > Settings > Application manager > Gallery > Clear Data.
Don't worry, this will delete all the picasa album photos from your phone but they are not deleted from Google + so you will get them back. It does not delete any photos on your SD card.
Then go back to Gallery > menu > Settings > Choose your google account to sync > Resync picasa albums (at the bottom). This will take awhile if you have a lot of photos in your picasa / google+ albums so you might want to make sure you are on wifi.
Then they should all be back, minus the offending photos you deleted off Google + earlier! I really hope that helps you. I searched for ages trying to find the answer to this before working it out myself!
Oops, meant: in picasa tool, discovered auto backup, want to delete entirely, in fact, I'm so irritated by all the synced photos involving picasa, I'd like to delete all under guise of picasa- you know how to delete this large autobackup album of photos?
I've already disabled G+ long ago. I haven't done a thing from PC but have unchecked sync p.web albums (gmail accounts still not having sync on- I miss that!), from app mgr, all, gallery, cleared data c cache is auto done) so I've got to point in gallery, I'm no longer seeing pics with picasa icon on them.
Somehow, I feel this is temporary- even tho I've got sync off, G+ off, once I figure out how to delete autobackup, I'll be golden. There may be a menu button, delete album option but I did lots of this tonight, needed to first see that gallery was cleared from having picasa iconed pics. At least, there's progress- using bright kernels from forum help, I'm in far better shape than when I first arrived to find solutions! Many thanks to all !
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