First, to have something executed regardless of pass or fail of the test you need to override the CleanUp method in code. Here's a sample:
.ExecutionContext.TestResult.Result == ArtOfTest.Common.Design.ResultType.Fail)
// The test has failed. Perform any action needed on failure.
For getting the currently logged on users ID, unfortunately there is no standard, even in the ASP.NET world. There are many ways people can get logged on and many ways for the web server to keep track of which user is logged on. Only your developer can tell you how it keeps track of who is currently logged on to that session. I take it you couldn't simply keep track of which user ID you used to login at the beginning of the test?
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