If you are thinking about extending the capabilities of Team Foundation Server 2010Build, surely you will find some glitches in the road (being politically correct at the time said, because it is a stack of problems at the very least).
As well, the tfs build extensions have arrived to solve such problems. For example, there are activities to run code (code metrics) metrics, create ZIP files, execute commands of RoboCopy, etc.; We are going there all in apothecary.
Highly recommended to give a back and a look to access and provide feedback on the official site of CodePlex:http://tfsbuildextensions.codeplex.com
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