Hi Matthew,
It absolutely is an option to set the height specifically - just set it in your css.
That said, In recent builds there were updates to this JavaScript code, and it should be working correctly.
As long as your setting is a number (ie, no px or whatever unit) and as long as all the controls are on the form in the normal way (ie nothing being created in hand-code) it should work.
So if you have a wizard that is not working, please duplicate the issue in an example app and post it to me please.
Cheers
Bruce