> This isn't actually true though. You can delegate to the default window proc, and only customise what you want.

Yeah that was my memory of doing this stuff. You basically just added what you wanted to the case statement (or other hooks depending on your framework). Then dump the rest onto the default proc. The default 'wizards' usually made the standard petzold structure for you and you didnt even really have to think much about it. Now if you were doing everything by yourself just make sure you read the docs and make sure you call the default in the right cases.