...My game saves and loads just fine using EDGE firmware 1.5.
What do you mean it freezes after saving? It doesn't for me.
The only bad thing I've encountered so far, is, if you save the game, and select "Save and Quit". It takes you back to the main menu, and when you try and select your save again, it does the exact same thing as before. The menu freezes. So just don't "Save and Quit" and you should be fine.
Also, I'm using the AR code fix. Not the patched rom. I tried the patched rom, and I get white screens on boot up. The AR code works perfectly.
So I guess the game restarts itself of any codes/cheats when you do, "Save and Quit".