Based on your description it seems like the connection is lost after recording starts. This might be caused by many reasons, but most often it is due to:
1. Wrong app configuration. Please verify that you exactly follow configure your application to be testable
article. Note that when targeting iOS9 device, you have to ensure some additional details concerning the app identifier.
2. Connection loss might also be caused by Wi-Fi connection settings. Have you tried recording using USB connection instead?
3. Older version of Test Studio - please ensure that you are using latest version of the product.
If none of the above helps, I am afraid that we will need a sample that replicates the problem. If your app contains a sensitive information, you can assemble a dummy app that replicates the issue and send it to us for investigation.
Telerik by Progress