First of all, the video. Yes, I thought it was very useful. May I suggest a section on the website for instructional videos?
As far as the new design mode goes, I am certain that users will find it of great value, but a word of caution and that is that unconventional layouts do confuse many users, and even such mundane issues as to which is the default button, whether ‘OK’ is the leftmost, whether buttons are centred or justified etc, can make a huge difference to the acceptability of a dialog. Matters are complicated by Microsoft’s propensity to change their mind about such things from version to version in Windows! The User Experience Guidelines are not updated frequently enough in MSDN.
The ability in design mode to change the button height seems to me to be very valuable, and it seems to me that as this is can now be done, perhaps it could be a facility in %bt, and even if available in %bt, why not also in %tt and %bb? (so they can be all the same height).
The new multibutton format looks very interesting, and especially the availability of some standard, professionally-drawn, icons in 16x16 and 24x24 is a big plus. Those professional icons have the potential to be recognisable when inactive (greyed) which is something that one’s own icons don’t always achieve when using the automatic generation of the greyed-out state.
I looked up TBSTYLE in MSDN, and the TBSTYLE_LIST looked interesting (with text alongside the icon as in %bb) and particularly TBSTYLE_TRANSPARENT, which would be a great complement to %ib.
Eddie