Thank you for the writing.
I can confirm that the described issue appears in RadTreeView. I have added in our Public Issue Tracking System
. Feel free to add your vote for it here: http://www.telerik.com/support/pits.aspx#/public/winforms/14804
As a workaround you can manually set the RadTreeView's DropHintColor
property to the desired color.
I hope that you find this information useful. I updated your Telerik points. Please excuse us for the introduced inconvenience.
the Telerik team