Yes, you can execute a large test list. In theory a high number of tests within that list should not adversely affect it. There is no additional configuration necessary.
To properly diagnose the failure, we will need more information. The next time you receive an error, please gather the log and step failure details for us to inspect.
Of course, if you are able to reliably see the same error, we'd like a copy of the project with instructions on how to reproduce it.
the Telerik team
Check out the Test Studio roadmap
to find out more about the new performance testing functionality coming in our R2 2011 release this September!
Have you looked at the new Online User Guide
for Telerik Test Studio?