The example you provided worked fine and there didn't seem to any difference between your code and the code I had written.

It turns out the issue in my instance was the result of the objects only being created on Page Load when there was no postback. Due to the construction of the site we're building, postbacks (mostly asynchronous) occur fairly reguarly.

I've changed the code so the editor is created on all page loads regardless of postback state.

this resolves the issue (though i may need to address functionality of the page.

thanks,

Dan