Thank you for your post.
First of all, please update to our latest version, currently Ranorex 8.0. Support for Ranorex 7.X will be dropped soon.
"Doesn't work this way. Version 7.2.1 is not able to find components using UIA paths if current mode was set to WpfImrovedOnly and vice versa.
At least in my case (WPF, Telerik)"
Unfortunately, this can't work. If you are using UIA paths, you will need to set the WPF mode to UIA (only) either within your global Ranorex Setting or within a code module.
As for the SUT hang:
Please create a support query, with detailed instructions on how to reproduce the issue: https://www.ranorex.com/support/support-query.html
Technology specific object identification, supported applications, web technologies, and 3rd party controls.