I was able to solve this problem by doing the following (assuming you are using VisualStudio 2010 plug-in):
1. I create multiple testsettings files (Rapid, ProdSupport, Production)
2. in each testsettings file, I set the BaseUrl field to my domain (i.e. https://rapid.testsite.com
). BaseUrl is found in Test Settings > Telerik Test Studio > Web (tab) > Navigation > BaseUrl.
From here you can use the commandline argument /testsettings in your mstest <buildargs> tag to drive the location of the tests to be run.
For my tests I have every setup step, which always includes login, get the BaseUrl from ArtOfTest.WebAii.Core.Settings.Current.Web.BaseUrl. That then looks in to our user database to get the password for the requested user and logs in that user in the correct environment. Knowing which database to use depends on the subdomain of the BaseUrl which I strip out through code.
You can replicate this process using an XML file but you would have an XML file for each environment.
What I have found is that, though my recording settings are set to ignore the baseurl (Elements Page Compare Mode = "RelativePathOnly"), when recording modal and radwindows (and sometimes objects) the baseurl is still included in the object search definition. This does effect recording frame interaction causing me to have to go back and edit the lookup definition for every frame I record, even when recording it for the second time to edit a test. This may be a bug which I have not yet had time to report to Telerik.
I hope this helps.