Bobbles Yes, it is good practice to post separate suggestions as new threads. This way other users may participate in discussions they are also interested in.
I am not sure what you mean by ID in that case. If that is something that only exists in database, this will not be of much help if file will be renamed. For the application this will be just a new file, and there will be no way to know that is has something to do with other file that has just disappeared (because old name does not exist anymore).
In any case, renaming is extremely rare case. I don’t know if you noticed, there is still no file rename funciton in Tonfotos, but guess what? No one seems to care. That is why it still was not implemented.