Had a similar issue last year, but ours wasn't stuck; it just wouldn't go all the way back in and lock for travel, slamming open and shut on every curve until I blocked it. The guys at BCS fixed it, and I think they removed the wood ceiling molding at the top that hides the mechanism, so they could swing the door out to make the fix, but I'm not certain.
Removing that molding might give you more visibility at least and that is always primal to engineering a fix. I know on ours they cut an inch or so off the back vertical door edge so the thing would roll back far enough, so something inaccessible deep inside must have fallen out of place. Yours certainly sounds like a jammed guide roller; maybe removing molding would allow a rod of some sort to reach back and pry it loose enough to move the door out, or give you a better grip somewhere up along the track.
Like Jerry says, give BCS a buzz. They've been there, done that many times.
Joel