I just tested the scenarios and I was not able reproduce any of the issues:
For example, when a floating UI is present in the document, invoking
var firstBlock = radRichTextBox.Document.EnumerateChildrenOfType<FloatingUIContainer>().First();
successfully removes the block.
Could you send us sample applications reproducing the issues, accompanied by specific steps to reproduce them? Specifically for the second issue, how are you trying to move the block, by code or through the UI? What is inside the block and does it handle user events in any way?
Want to extend the target reach of your WPF applications, leveraging iOS, Android, and UWP? Try UI for Xamarin
, a suite of polished and feature-rich components for the Xamarin framework, which allow you to write beautiful native mobile apps using a single shared C# codebase.