When you bought Pro, you would've recieved a link to your Pro personal download page. Are you trying to download from that page, or are you going to the Pro support page on the LW site?

Providing you bought Pro from the official site Lime Wire » Official Website & Free Download, BitTorrent « & payment was made to LimewireLLC (if you emailed LW support then I'm pretty sure that you do have an official version, but just checking)...send a PM to limenathan & see if he can sort things out for you.
limenathan (click on link)