Hi Jenny,
Maybe if you started a new thread dedicated to your particular difficulty it would get more attention.
Lightroom definitely has a bug in it - thinks it needs to rename for uniqueness when it doesn't.
That said, I've no idea how to fix it, except it seems *maybe* root of problem is in catalog. Consider rebuilding somehow. e.g. if there is a backup which doesn't have the problem, then you could fall back to it, then re-import newer photos. I dunno if it's a prefs thing, I suspect not, but you could always try renaming .agprefs file (without Lr running) to double-check. Ditto for previews and acr cache - maybe you'll get lucky, but I doubt it.
I mean, if you start a new catalog, then import into it, do you still have the same problem?
Personally, I rebuilt my catalog using LrFourB in conjunction with a half-dozen other plugins, but it's far from a "turn-key" method, to say the least, so not really recommended unless you really like to roll up your sleeves...
Not sure what else to say - Adobe has not acknowledged the problem, yet (on the feedback forum), but you and I know: it's there 
. You may want to go add your .02 there if you haven't already:
Cheers,
Rob
