P: Ability to assign a second monitor with more than 3 monitors

You can always move the primary LR window over to another monitor, but I'm not sure that will solve your problem. Or you could disable the notebook's internal monitor so one of the external monitors becomes #1. Or perhaps you can find a video driver which will allow you to rearrange the monitors.

Thanks Marc. You may be right, but I cannot find a way to change the assigned monitor number. #1 is my notebook internal monitor. #2 is my primary external monitor, and #3 is my secondary external monitor. I want to use #2 and #3, but LR is using #2 and #1. They also have all different resolutions, and I cannot physically move them around. Any ideas?

Under Windows, LR will use the monitor defined as display number 2, so you can set the monitor you want to use as the "second monitor" in the Display settings of the control panel.

Marc