Amitoj,
1) The Agentry Editor has a teamshare repository for automatic merging of code. You can also export the merged "master" and checkin to any version control repository.
2) The Agentry Editor will check your Agentry definitions and generate warnings and errors. Unfortunately it does generate a number of false positive warnings that can be ignored but does also flag some important ones as well (warning and errors).
3) You will need to look at third party tools for this. Internally I believe we are looking at Squish as a functional test tool for use with the Agentry clients. You will have to evaluate tools and decide what works best for your requirements and budgets.
--Bill