Just wanted to say thanks, this post is still useful months later! I'm in basically the same situation as Guy, moving to Windows 7 and moving from PowerDesk to DirectoryOpus, but not wanting to lose Dialog Helper. Direct Folders looks like it should do the job, and it works with DirectoryOpus.
BTW, there is a new version of PowerDesk (v. 8)
that works under Windows 7. But I've grown tired of PD's flakiness; it hasn't been maintained well in recent years, and that's why I'm going to try D.Opus (at twice the price!).