I was playing as Poland and noticed that I was losing thousands of infantry equipment...In 1937.
There was no warning for any low supply, as a matter of fact, everyone was supplied just fine, but still I kept losing infantry equipment over time for no reason, and I ended up being unable to actually put out any troops because of that. I used only RT56 and RT56 Expanded, NO other mods. I started a new game as Iraq to test it out, and I was once again losing equipment even when all my units were in a plains tile. I try again without RT56 Expanded (just the base RT56) and now it works just fine.