Level of DifficultyEasy
Time to do repairLess than 15 mins
Age of Appliance5 - 10 years
Once I figured out how to get the endcap off the roller track (allow several minutes, because it was designed by some dork), I slipped the old roller off the track, put the new roller on, and clipped it to the rack. Then I put the track cap back on (really easy once you've figured out how to get it off) and it was good as new.
As for how the cap comes off, it's difficult to describe. But it may help you to know that the cap, despite what it looks like at first, is actually surprisingly long and folded on top of itself. Pulling it directly out doesn't work; you have to unfold it before there's any chance of getting it out.