Okay, the plot thickens...

So I tightened up and repositioned the skewer on the back wheel, and seem to have gotten it properly centered... no more tire rubbing, although the rear tire seems to be awfully close to the seat post and the stays in its "normal" position. But in working over the bike and checking the seat stays for cracks I discovered two dents on the underside of the down tube - one about the size of a dime, the other smaller - I hadn't seen them when I looked over the bike before purchase because the paint is not compromised at those points, but I can feel them when I rub my hand along the underside of the down tube. I'd say the depth is a few mm.

I took a decent-length ride on Saturday and the bike did... okay, but still feels kind of wonky. I'm having trouble adjusting the FD to keep the chair from rubbing at one point in its revolution when on the larger chainwheel. I wouldn't be surprised if the BB needs to be overhauled, but don't know if that's causing the problem.

So now the question is: is this frame safe? Do you think it's been compromised by whatever caused the dents? I can't see any cracks anywhere, and the frame looks straight. I'm seriously bummed about the dents, but if the bike is otherwise ok I'll just write it off to my eagerness to get that model, and continue refurbishing the bike. If the frame is compromised I need to contact the seller right away and try to get my money back. I didn't really want this much of a project bike, and if it needs serious work I've spent too much on it already to justify that kind of expense.

Any advice? And thanks for the advice so far.

Roy