P: Export As Window is outside screen

It probably is moveable but you can't get to the top of it to drag the title-bar, right?

Is the scaling larger than you expect on your MacBook screen, so the issue is that the Thunderbolt scaling is being used on the MacBook that is not such high density display, or are they both very Hi-DPI so the scaling is appropriate and the only issue is the window isn't all on screen?

If I ever have this situation on Windows I can use Alt-Space-M to bring up a window-positioning menu and activate the Move command that would automatically move the window to be all on screen and then let me use arrow keys to move it around. I suppose a Mac doesn't have similar functionality.

The window scale seems correct.
It's only visible on the small screen, mainly off-screen, and is neither resizable nor movable.

It should open on the same screen as the main application, or at least be movable.

Sorry, a bit of context on that screnshot: I'm using two monitors there, the left is my MacBook, the right is my Thunderbolt. The Export window appears on the wrong monitor and also off-screen.

Is the problem that the window is being scaled up as if its on the HiDPI monitor but it's not, or is part of the window on one monitor and part on the other?

I have this problem too. I can't reach any buttons, can't drag the window; I can only press Escape to close it.

OSX 10.10.4, 27" Thunderbolt, 15" MacBook Pro Retina.

Screenshot: