Make sure you replace the CuteChat.dll and all the CuteEditor client scripts when upgrading.
Also make sure you clean up your browser cache.
BTW the version 5.0 is out.
Please try this new version.
Demo:
If you still have problems, please let me know.
asp.net Chat http://cutesoft.net/ASP.NET+Chat/default.aspx
Web Messenger: http://cutesoft.net/Web-Messenger/default.aspx
asp.net wysiwyg editor: http://cutesoft.net/ASP.NET+WYSIWYG+Editor/default.aspx
asp wysiwyg html editor: http://cutesoft.net/ASP
asp.net Image Gallery: http://cutesoft.net/ASP.NET+Image+Gallery/default.aspx
Live Support: http://cutesoft.net/live-support/default.aspx