FYI: New trainer is working fine for me. Now if I just had a way to get whatever gun/sight combination I wanted whenever I wanted, then I would be extremely happy.
Just before the second trainer was released, and the first trainer was not working, just for fun I downloaded CoSMOS 6, and played around with the ammo counter. It looked like there was one memory address for each weapon, and then a third memory address for whatever weapon was currently equipped (presumably this was the actual counter that tells you how many rounds are in reserve, as it appeared to always inherit its value from the memory address of the weapon that was equipped). Of course, the memory addresses change each time you launch Homefront, and since I never bothered learning enough about CoSMOS to know what to do with memory addresses that change each time an EXE executes, I didn't really have anywhere left to go after that. Wasn't difficult to figure the memory address out, however, so if I absolutely had to, I would have been able to do that whenever I needed to.
As for figuring out how the health works in Homefront via CoSMOS, my knowledge of CoSMOS is basically "search for this number", "search for a change to this number", search for another change to this number", etc. Without knowing exactly what the health counter reads, then with my current knowledge of CoSMOS I would have no guarantee of finding the memory address/addresses related to the health, so sticking with the CheatHappens trainer is about the best I could do.