Hello fff fff,
I was not able to reproduce the issue with the mentioned version of RadEditor for MOSS(188.8.131.52). For your convenience I attached a small movie with my test. Please tell me, if I am doing anything wrong.
One thing that I can suggest you is try if upgrading to newer version of the control will solve the issue. You can find the instructions in the following article http://www.telerik.com/help/aspnet-ajax/upgrade_to_a_newer_version_of_radeditor_for_moss.html
Also please provide me with the following files. ConfigFile.xml, which is located in the /Program Files/Common Files/Microsoft Shared/web server extensions/wpresources/RadEditorSharePoint/184.108.40.206__1f131a624888eeed/Resources/ folder and the ToolsFile2.xml which you are setting in the code. They might help me in reproducing the issue on our test server.
the Telerik team