I live in the US, but I can't find an opera browser US rom. is everyone in the US using the euro or jpn version when using it in conjunction w/ their R4 and ez flash 3 in 1?
I know for a fact that there's a Supercard patch out there, I'm able to use my SCDS1 (Slot-1) and SCLite (Slot-2) together to run the browser perfectly.
The DS Opera browser supports WEP but not WPA I believe.
Try switching yours to WEP, or even turn the encryption off, although I wouldn't advise that. Just look up your router manual for instructions.