I just brought my 3017 371 rebh home and had the same problem. I agree it is a design flaw. I went to Lowes and bought some sliding door channel in color of brown. Took their bottom brscket off and added mine. Works great and is solid. I will post a pic as soon as i can.
The door guides are extremely flimsy, nothing real solid for the screws to screw into. You should have received a pin maybe "U-shaped" that is used to hold the doors closed, if not buy an inexpensive child-lock at Target that will capture both doors to hold them closed while traveling.
The holders on my closet doors were also problematic. Almost every trip the doors would come out of them. I purchased a similar looking piece from Menards to replace the factory holder. It was sold in a 36" length designed to be used as a "no tools required" door bottom sweep. I cut it in half and put about 6 screws in the back to hold it in place. It was about $12. Haven't road tested it but seems much stronger than the factory holder.