1. How lightweight is the program? Better to have multi-core CPU's?
Very lightweight, I have 2 zoomer docks with 25 shortcuts and 3 docklets running, 2 tabbed docks, 7 tabs total, numerous shortcuts. OD using only 44 meg of ram with it set to use ram, it can be set to be more ram friendly.
My system, 2.4 gig celeron and 1 gig 333 ram that only runs at 266 due to the celeron and OD runs very well.
3. How much control over its behavior do you have?
Total.
4. Do windows, when expanded to being full-screen, recognize the dock as something to work around?
OD can be set up various ways, on top, bottom, auto hide that with moving cursor to dock screen edge will bring it to the front, you can reserve screen edge so a maxed window will not cover dock.
5. Can it be used along with a taskbar (particularly just as a quick-launcher for programs instead of showing active programs)? Or is it better to use it as a task-bar replacement?
Some use it as a taskbar replacement, I however do not hide the windows taskbar.