I am sorry, I forgot about the awkward version number displayed in Programs and Features. It doesn't allow number greater than 125 in the Major field so we opted for the mangled numbering scheme as an alternative.
test Studio 2011.1.502.0 is known to have many serious flaws. I highly recommend going to our latest internal build, 2011.1.809 instead. It is much more stable (and has a few new features also).
I did run the same set of tests on 2011.1.502.0 (though I had to re-record new ones because tests made in 2011.1.809 are not backward compatible). They all ran successfully, just like using Test Studio 2011.1.809.
the Telerik team