Before embarking on the migration, we carefully read Microsoft's books on Windows design guidelines and standards. As it turned out, this was a very important step for us because it caused us to produce true Windows applications from the beginning. It offered great improvements, but there were rough spots. True Windows applications require a programming style different from that used for DOS and UNIX applications. It is event driven programming.
Users can freely move around multiple screens in the program.
This requires very extensive checking to assure all required information is properly entered and edited. This is why it takes so long for new Windows applications to stabilize. We released our last major application in 1999. The migration is now complete and running smoothly. Consistency is a big benefit , if the developer uses MS design guidelines.