the auto detect routine in the firmware isn't perfect, but akaio offers you the option to manually set it. checking advanscene's release list the rom is 512kbit save type. so first make sure that is set up correctly. i have been told that bleach will corrupt save data on the U release on all flash kits due to some problem with the header. you need to unpack the rom and patch in the japanese header to fix this problem. i haven't done it so i can not provide more information.
goodluck
-another world