Have you installed your license yet? You should have received an email with a license key and instructions on how to install it. If you did not receive such an email, or if you are having trouble with the instructions, please log into your account at https://portal.nextlimit.com and file a request for technical support.
i got the serial key, and the password to login. i followed the instruction to install and i activated my serial number, yet, i still got the watermark on my image. do you think i need to re-install it?
Sorry, but I don't know -- this forum is about the Maxwell for Rhino plugin, not Maxwell itself, which is why I suggested that you contact tech support through your portal account. You could also try posting the question in the main Maxwell forum, but I suspect you would still end up needing to contact tech support.