If I am understanding you are saying dropbox is syncing photos TO your phone.
If that is in fact what you are saying then it's most certainly something else as he photo sync feature on DB is purely one way, phone to dropbox, it itself does not sync down, you need 3rd party app like dropsync to achieve that.
One thing you may in fact not know is that the native android gallery is deirectly linked into your google account and any images in your drive or picasa folders are on your phone, now you say the have the dropbox log. That makes little sense, you would most certainly have to of installed a 3rd party app to sync down and even then the apps do not change logos in your gallery. I use dropsync to bring folders down and it does not do that.
What you can consider as a band aid is to install quickpic, I find it far superior to the android gallery, in part becuz I do not like that picasa sync thing, but its also just a shat lot faster, and has 1 feature that I feel is moronic to of not been included in the native app, and that "Hide Folder", think its actually referred to as blacklist, now as you have a custom rom you can easily freeze the native gallery to keep any wondering eyes from getting to it, or hell just delete it altogether and just have quickpic hide the folders.
Unlike other apps that add a .nomedia file into the folder, which work, but it also blocks most apps from detecting all types of media in those folder, including video and audio, most cases not an issue. Quicjpic simply just places an internal exclusion filter on it.
