Hello Tony! I had to replace my plastic drawer channel holders too. I also installed some plastic horseshoe type clips on my draws to help them stay closed.
I think what you are talking about on your draw situation is the built in securing clip on the bottom of each rail so the drawer will not open up while driving. On my drawers I have to lift up (about 1/8 inch) and then pull out. I think what you have is normal. I added the horseshoe clips to my draws after one trip over the George Washington Bridge. As I was driving I noticed (to late) all of the wheel Hubcaps on the side of the road right before I hit all of the 6” deep holes! Every drawer and cabinet opened up and everything wet flying out. I haven’t taken that Route since. Other than that my Unit has been a peach to own. Even with the new mix of gas that we are getting in Connecticut I am managing to average around 13 MPG with the 2003 6.0 Chevy.
As I was de-wintering the unit I was wondering to myself that when the time comes to clean my Refer exhaust stack how am I going to get to it. The only way looks like you have to remove the unit out of its space to get to it, I looked down from the top and I could not see anything, plus it was 3 ft down. Here is what I did; I believe that you have the same set-up as mine. The cabinet over the fridge, you can remove the back of the cabinet and you are right at the back of the Fridge , you can get to the baffle for removal and you can run a brush down the chimney right from there. When you go to replace the back of the cabinet install a removal panel so that you can clean it out as often as needed. Most of what I have read on the forum people are having to remove their units for this. I think we are pretty lucky have this cabinet above ours.