Nope, fights against the AI are completely smooth. The problem is forwarding the port and attempting to use the P2P function doesn't work, and my only option is to not forward the port, ignore the warning, and experience massive lag.
Initially I was getting the message to open the port, and the few fights I could get were very laggy. I opened the port and now it just stays as a black screen whenever I attempt to fight another person and I cannot get a fight. Is there any fix for this? I am on windows xp and just downloaded the game today.