Thank you for contacting us.
We are aware of the described problems and currently working to resolve them.
In particular adding our controls in the VisualStudio 2015's toolbox (and allowing to drag and drop them directly) is already addressed and it will be present in our next release of "UI for UWP" suite. Next release is expected by the end of next week.
We are sorry for the inconvenience caused.
Do you want to have your say when we set our development plans?
Do you want to know when a feature you care about is added or when a bug fixed?
Telerik Feedback Portal
and vote to affect the priority of the items