Create a password-protected 'user area' page to interface with Parallels Plesk web hosting software

We are offering a hosted, 'build-your-own-website' tool using the web hosting automation software called Plesk Panel (by Parallels), including their proprietary, wysiwyg web site creator (called Web Presence Builder) that is pre-integrated into their hosting control panel: [login to view URL] Our intention is to serve website owners who have no experience with web design/hosting and would otherwise be frustrated with GoDaddy, yahoo, etc. - In other words, those who simply want to log straight into an 'idiot-proof' CMS and design/manage/publish their website content. Our entire backend is in place, as Plesk Panel is pretty much an 'out-of-the-box' solution for serving small website/hosting clients. Also, our front-end website is already designed and built. Here is where you come in: Our intention is to 'insulate' our clients from options and hosting functions inside their Plesk hosting control panel that are beyond their expertise (DNS, ftp, etc.), only giving them access to the functions that we are offering them (primarily, the website builder tool). In the ideal scenario, the customer will login to their (Plesk Panel) account via a login form on our front-end website, which will interface with the Plesk Panel login page and pass through the credentials, but then redirect them to a simpler 'user area' page (which we've already designed) outside of Plesk Panel, **while still maintaining the Plesk Panel session**, thereby avoiding exposure to the actual Plesk Panel and all of the 'extra' hosting options it contains. With the Plesk session still maintained, the client could select any of the few options offered in the 'user area' (i.e. website builder tool) and it will launch in a new browser tab as it normally does if selected from within Plesk Panel. I'm very interested in your suggestions as to what the best solution might be. We can set up a call and screen-share, and actually walk through the software and details. Parallels has an API available, as well as advanced documentation. I have also found forum articles involving discussions by other Plesk users looking to do the same thing. All of this should help in the process...