Change style of wordpress plugin 'Business Directory Plugin' and add registration

We are running a wordpress plug in 'Business Directory Plugin' we need some minor style change made to it and a functionality addition. We need to give users who submit their listing in the business directory the ability to log on to edit their listing. as an additional task we also want to provide for them their own unique affiliate type url. [login to view URL] which they can send to their contacts and anyone who uses that url to visit our site a record will be made and recorded in their account