Redownloaded and it still won't work.
I'm using R4 flashcart with firmware 1.18 patched with Yasu's cheat fix.
The cheat file I'm using is 08_08_08_CHEAT.DAT.zip and according to the page, it was uploaded on 09 Aug 2008 05:42.
EDIT:
I tried the latest USRCHEAT.DAT and it worked. Sadly...