I use both my tube and tray A-MAZE-N smokers without any mods.
I just remove my drip tray and smoke box and rest on my element so that it is close to the drain hole for air flow.
I have tried different locations from on the floor to on the lowest shelf rack, but have found that I get the best results by just resting the bottom of the smoker between the elements and the top on the front of the smoke box rack.
I can also tell you that I switched from this torch:
Self-igniting Butane Micro-torch
To this one and it made lighting my A-MAZE-N smoker WAAAAAY easier.
Mag-Torch MT535C Self-Lighting Regulated Torch
I was constantly battling with that little butane torch to keep it lit. But, I have not had to relight once since switching to the propane torch.
For the tube, I remove my smoke box and rest the tube on the front of the smoke box frame and the back of the tube on the #3 element. This rests right about the drain hole where air can come in. Since I am cold smoking I remove my drip plate to allow for more air to get to the drain hole.
I had some trouble with my earlier tests, but I think it is because my mini-torch was not getting the pellets lit adequately enough. My kids got me a propane torch for Christmas a couple years ago and I have not had my A-MAZE-N smokers go out on me since.
I slight wind is necessary to get some air flow though. Otherwise others have used fish tank aerators or even a James Jerky Dryer if you have one to keep air moving through the smoker. The A-MAZE-N going out on you is easily remedied with a few slight tweaks that do not require modifying your smoker.