For example, if I'm customising the Windows common file dialog to add a preview pane, the ideal is to try and make it look good for every platform by tailoring it for each version of the OS. This isn't as hard as it sounds though, because the file dialog has only really had two forms in the last decade: "explorer style" from the 95/98/ME/NT4.0 era, and "2000 style" which is nearly the same but with a places bar down the left. For Vista and newer MS have introduced a new more advanced file dialog API, which allow Windows to natively give us all the features we want without having to customize anything.
So hopefully when I get these three done we should have file dialogs that look seamless in every supported version of Windows, and which will continue to look good for every version of the OS into the future. But without the new versions of the SDK, I can't easily do anything other than a 95/98/ME/NT4.0 style dialog.
Do you see my problem?