it's hard to say anything definitive without looking at your test. One thing you should definitely look at is whether your test is written is such a way as to wait for elements to appear before attempting to perform actions on them. Please go ahead and paste a test that you have trouble getting to work. It would be able if we're able to run it (i.e. the app it tests should be publicly available) - that way we'll be able to easily troubleshoot the issue.
All the best,
the Telerik team
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