Shower Door Roller Issue
We had similar issues with our 2012 Solera. I don't know if you have the same or a similar shower door, so don't know if my solutions will help your situation.
I determined that the shower door was not staying latched during travel, was sliding back and forth in the roller tracks until the lower roller "found" the "removal slot" in the lower track, popped the plastic retainer out, and jumped out of the track. (This occurred during our test drive, dealer said "fixed" when we picked it up - NOT!)
First - I adjusted the rollers such that the door effectively "hung" from the upper rollers - lower rollers basically running on the top of the guide. With this adjustment, the door at least did not jump out of the top guide - stayed "hung". See attached picture of one of the top rollers.
Next I added a piece of 1/4 inch "drip irrigation" hose to the door where the latch engages. Attached with "GOOP" (taped in place until dry). This resulted in our latch working perfectly and has not released during travel since (40K plus miles, including the ALCAN hwy).
Finally, I made a piece to replace the plastic retainer in the bottom track. I used aluminum cut from a duct I had in the basement. I made it longer than the plastic one, bent a sharp angle in it to hook onto the edge of the bottom track, shaped to the outside of the track, "GOOPed" the edges and screwed it in place with the screw from the original plastic retainer (which I suspect had been damaged by the "bounce outs" caused by the latch not working). Have not had a roller escape either track since doing this.
I believe the rollers are 1 inch rollers - I would check Amazon, Loews, Ace, Home Depot for something equivalent if I broke one (which I haven't yet).
2012 Solera "S"
Calif SF Bay Area