Ajay,
1 - In general, there is no direct communication with the Schematic system to Windchill in the library area. Your observation of the Cadence connector is valid; there is however only a discussion @ PTC about doing the same thing for Mentor. If your company is interested in this, I highly recommend that you provide feedback through your PTC Sales Representative or VAR that this is something of interest. PTC will not finalize their development of this into a product without direct customer request.
Library metadata is held in a WTPART in Windchill that is basically an extracton of what you have created in Mentor.
2 - A custom integration would be possible, but it is a VERY heavy customization. In my experience, you should NEVER attempt a customization.
3 - No. See answer #1.
Can you explain why you would want to integrate your ECAD library data directly into Windchill? What are the business advantages? What doesn't Mentor do that you would like to see done?
In general the thought around this area is this; Mentor manages their own data very well. There is no reason to manage Mentor data by a third party. There is a need to represent some of that data in the PLM system, but the need must be compelling. Usually all of this is already done and managed in the native ECAD tools, and we in the PLM space, just want a "window" into the information.
I hope this helps; please call me with questions.
