customize Joomla component (DT Register)

The open source component DT Register ([login to view URL]) allows web users to register themselves for events offered on a Joomla CMS website. This Joomla component has required fields which my client does not want to be required. Custom PHP programming needed to reduce the required fields to only include Name and Email. Component must still integrate successfully with online payment processor (e.g. PayPal) and continue to integrate with JEvents (& the entire Joomla site). Examples of past PHP coding helpful. Happy Bidding!