You cannot re-arrange in Configurator UI. One workaround is to open the gpc file with a text editor, and re-arrange the order of elements "canvas" under element "tabnavigator". You'd better to backup the gpc file before editting gpc file manually. You should be careful when editing the gpc file. If you do something wrong, the panel will not be opened correctly.
Thanks, I'll make a backup then give it a try.