Okay, so with that said, chairs moving is a part of daily living, and while it might be nice if they were to do so more quietly, the fact is that apparently the sound is bothering you. And unfortunately, that's really a problem for you (remember, they don't see this as a problem). Have you taken any steps to see what you can do to reduce the noise in your unit? Or have you tried using a white noise machine or other method to mask it?
If it were me, I think the smartest course of action would be to get one of the decorators catalogs, write a note on it that you'd like them to pick out an area rug of their choice no more than a certain amount of money, and you'll pay for it. While you shouldn't have to go $300 out of pocket for their decor, it seems like a small enough price to pay for peace of mind.
However, if it's more than normal living type noises (yelling, banging, music, etc), then you definitely have a right go complain. As a condo dweller and landlord here's what I'd recommend;
1) Go talk to your upstairs neighbor again. Tell them you don't want to complain to the owner or association, but you'd like to get along and figure out how you can make things better.
2) If 1 doesn't work, discuss the issues with the owner of the rental unit. The owner should have something in their lease about the quiet enjoyment of other residents. Ask the owner to talk to their tenants.
3) If 1 and 2 don't work, go back to the condo association and file a complaint. They should discuss the issue with the unit owner.
4) call the police. There's not much they will do, other then tell the renters to be quiet. Although, several police calls would be grounds for the owner of the unit to evict the tenants.
At the end, I sold my condo and moved out.
Sorry, I don't have better news for you...