I have been able to reproduce this consistently. It's a very generic test and it basically follows Gail's steps verbatim, so I'm not sure how you have not been able to reproduce this. I did the test using an Amazon AWS EC2 instance, which you can also use to easily reproduce this problem. And my C# test project simply opens an IE browser and browses to https://www.google.com/. Here are the exact steps I took:
1. Launch a new Windows Server 2012 R2 EC2 instance.
2. Disable IE Enhanced Security Configuration in Server Manager
3. Install the .NET Framework 3.5 Features from Server Manger Add Roles and Features
4. Install Telerik Testing Framework 2015.3 using TestingFrameworkFree.2015.3.1015.exe
5. Install NUnit 2.6.4 using NUnit-2.6.4.msi
6. Copied my project bin files to the instance and opened the project DLL in nunit-x86.exe.
7. Ran the test and it timed out. It opened IE and just sat there on the blank page. See here for errors shown in NUnit: http://pastebin.com/qjcMDQuq.
9. Ran the test and it failed again in the same way.
10. Installed Telerik Test Studio 2015.3 using TestStudio_Ultimate_2015_3_1015_Trial.exe
11. Ran the test and it worked. It opened IE and browsed to https://www.google.com/ successfully.
12. Uninstalled Test Studio 2015.3
14. Reinstalled Telerik Testing Framework 2015.3 using TestingFrameworkFree.2015.3.1015.exe
15. Ran the test and it worked again successfully.