Steps to reproduce:
1) Open any project containing at least one test in VS 2010/2012
2) Edit test properties of any test (for VS 2012 use documented workaround found here: http://feedback.telerik.com/Project/117/Feedback/Details/41122-cannot-get-to-ts-test-properties-in-vs-2012)

Expected result:
Test property list includes ReuseAppWindow as it does in Test Studio standalone

Actual result:
ReuseAppWindow is not available from the list of test properties