ObjectDock still seems to have many problems with screen changes, and I suspect they are all related. In my dual monitor config, whenever I log off and then back on, my tabbed docks are always on the wrong monitor now.

for example, what should be...
MONITOR A (primary, on the left)
tabbed system tray dock, right side, attached to edge/autohiding
tabbed dock (folders), bottom, attached to edge/autohiding
MONITOR B (secondary, on the right)
taskbar zoomer, left, centered
tabbed autohiding dock (links), top
normal zoomer (applications), bottom, centered
...keeps coming back as...
MONITOR A (primary, on the left)
(nothing)
MONITOR B (secondary, on the right)
tabbed system tray dock, right side, attached to edge/autohiding
tabbed dock (folders), bottom, attached to edge/autohiding
taskbar zoomer, left, centered
tabbed autohiding dock (links), top
normal zoomer (applications), bottom, centered
...so I have to manually drag the tabbed docks back from the secondary to the primary monitor and then re-enable attach to edge to return those docks to their proper position/functionality.
This is currently happening on Vista 32, but it always happened on XP as well, so I suspect this is a long-standing behavior problem with ObjectDock, as I can't remember a time when it wasn't broken this way.

I hope this helps troubleshoot the problem.