oh do-do.....as soon as I posted this I searched "drop and drop windows 11" to find that the bar stewards at Microsoft have removed drag and drop from windows 11.....yikes.
Hoever there is a work around -
1. Drag and Drop in Windows 11 Using Alt+Tab
This is one of the easiest method if you want to drag and drop files in windows 11.
Press, and hold down, the button on the mouse, to “grab” the file you want to drop.
“Drag” the file and press Alt+Tab button. Keep pressing Tab while simultaneously holding Alt and mouse button to navigate between files. Release the Alt+Tab button once you are on the desired location.
Now “Drop” the file by releasing the mouse button.
it does indeed work by opening up a window on your desktop and once you 'release' it opens the usual PM import dialog!