I don't know. Make sure the cheats are actually activated ?
I tried with R4 fw 1.17 (with bugfix2), enabled cheats like infinite bells, weather change, item change, and all was working properly (I had 99.999 bells, it was snowing, and I had items in my inventory). I have the ACWW with the following ID code : ADME 8F7851CB.
About eragon : it's a bit like final fantasy. When booting the game, the R4 has left some mess here and there, which - it seems -prevent the game from running. To "fix" that, they (R4 team) seemed to have put a "clean memory before launching the game" mode, but using this mode means the cheat engine is not used.