Just to clarify, the pins never truly clear the collars, they just come out of the slots in the pillar piece. If that makes any sense?
For now, it's best to just forget about the red stitch width lever. I think it's issues just may go away once the stitch selector issue is fixed. Best to handle one issue at once.
I think I may have a way to tell what's stuck, so you can focus your efforts. Let me shoot some video for you tomorrow.
Do you have skype and the ability to watch and send video by any chance? I just "upgraded" to it, perhaps I can sort of step through the monitor in a way....