The Dell Dock was made by Stardock specifically for Dell and Dell only. Dell provides the Support for it, not Stardock. It will work only on Dell computers. As for whether it will work on W8, you'd have to ask Dell.
As for making OD/OD+ and OD2 "more like the Dell Dock" there are contractual limitations, as I understand it. I'm not an SD employee, so take my answer as such and not an "official/authorized" answer.
OD does have the possibility to create "fly-out" subdocks. There are numerous Forum posts about this.
As for working with W8, it's a "not yet". There are other apps which do similar things. You can find out a lot more on the Support page:
https://www.stardock.com/support/?from=nav
and https://esupport.stardock.com/index.php?/Knowledgebase/List
which are handy urls to bookmark.