For Mathcad 15:
select the toolbar that is on the second screen by clicking on the top (blue) bar & drag it as you can any window.
If you drop it on the main Mathcad page it will stay in this shape.
If you drop it on the tool bar area it will change back to its 'docked' form.
selecting the bar at the left hand side allows it to be dragged & moved on the toolbar or undocked.
Mathcad should remember the last placement (it shouldn't need any file to be saved)
As far as I know the toolbars can't be moved on prime (but I only have MCP2...)
As I understand it you work with your laptop at a docking station and use a monitor with a larger resolution than your laptops screen.
When you undock the laptop while Mathcad is still active and the display is switched to the laptops screen, floating toolbars might be inaccessible.
I don't know of any way to bring them in view or reset the layout to a standard one (whatever that might be).
But if you close Mathcad and start it again you should see those toolbars floating at the very edge of the screen but in a position which enables you to take hold of them and drag them to a new position.
At least that happens when I try to simulate your problem by changing the screen resolution to a lower one.
I have an extra monitor at work, so when I'm docked I have two screens. When undocked I revert to the laptop alone.
When a program opens on that second (non-existent) monitor, I've found that there are right-click options from the taskbar that can make the program bring things into the only screen available.
Look at AutoIt. It can move windows to where ever you want them. There is a tool that can be used to find the window identifiers. I've used it with Wildfire to correct the problem it had with pop-under windows (dialog boxes that are created under the main window.)