9th week is gone and I explored XML for MS Visio Schema, EPS Schema format and issues for making PDF, SVG and Dia Exports downloadable. I had coded pdf,svg and dia exports that these will be prompted for download. It was working on my local wamp installation but not on demo server. Unfortunately that issue is still not resolved and after putting a lot of time on it I forget it and moved on.
For EPS schema, I found php extension pslib but unfortunately its DLL is not available. Though I can use this extension with Linux environment but I decided to use hand coded lib for Encapsulated Post Script files. Lots of information notes are available here http://www.tailrecursive.org/postscript/eps.html about Post Script documents plus programming commands. So, I am going to code it from Monday.
For MS Visio Schema, I consulted MSDN and will code the library class for generating its XML schema like I did for SVG Schema.
Hope for best !!