What I suggest you to do is upgrade to the latest version of the Light RadEditor for MOSS, which is 4.5.6. You can download the package form this location http://www.telerik.com/community/free-products.aspx
You can review the upgrade instructions in the RadEditorMOSS_4_5.chm, which comes within the RadEditorMOSS_4_5_6_Lite.zip.
All the best,
the Telerik team