Rust? Spider Mites?

[VickiC]

This little Catt has been struggling for quite sometime. When I first got it, I unpotted it and removed all of the dead roots, which were practically all of them. I repotted it and crossed my fingers. About 2 weeks ago I decided to unpot it and take a look. I saw that it was finally growing some new ones . Now, on to my question: the leaves. They have not looked good since first I got it (a 'rescue plant'), but now they look even worse. While I was inspecting each of my orchids this morn., I accidentally knocked this little fella out of his pot. The roots looked slightly better, but the leaves looked worse. As you can see, one leaf is totally yellow and most of the others have problems. Mechanical? Diseased? After I repotted it AGAIN, I wiped two of the leaves (top and underneath) with a kleenex. There was some rusty looking 'dust' on it. I've had no experience with spider mites, so they may be the problem, but this rusty-reddish appearance didn't look as I would think a mite would look.....like I said, it looked more like 'rusty dust'. I would appreciate it if someone would take a look at the pictures and give me your opinion and advice, please.
Vicki