It basically means 'feels right'. It just doesn't sit right with me. I don't feel right about this. I can't exactly put my fingers on it but it just doesn't sit right with me.
I agree. I see the image as one thing designed to fit into another - like your **** and the chair. But you look at it (or feel of it) and it seems askew. Some as yet unknown impediment is preventing the things from fitting together in/withproper alignment.