Button to Toggle "Replace Explorer"

Could someone give me a clue how to make a Button to Toggle "Replace Explorer"?

Well, i don't think this can be done but you can make a button to open the correct page in preferances by making a button and giving it funtion of
Prefs PAGE=misc


Vaguely related and possibly helpful (and possible not). If you want a button in Opus which opens the current folder in a new Explorer window, this is the command:

Explorer /e ,.

Be careful to include all the punctuation, including the full-stop.

If you really, really need to be able to toggle Explorer Replacement mode you could probably do it using some .reg files, since it is just a registry setting (the program associated with the Folder filetype) but it would probably be quite a clunky command.