MP277 10: 640 x 480 pixels.
TP1200: 1280 x 800 pixels.
Unfortunately the horizontal resolution is exactly 2:1 whereas the vertical is 5:3.
So if you choose to automatically fit the objects, there will be distortions. Circles will becomes ovals.
I think I would select a fixed ratio 150 % when converting the MP277 to the TP1200, and then manually adjust all the screen objects one by one (!).
edit: If you select the ratio 166% you should get the closest to fully filling the TP1200 vertically. Horisontally there will be some unused area. You can possibly move the screen objects around to make better use of the horisontal aksis.
Dont round up to 167% as some objects will be placed partially outside the viewing area, and thus will not be shown at all in the runtime.