I didn't quite understand the x2 part. On XL+U maps, with x1, it requires 2 screenshots per surface, and unfortunately, a thin strip remains on the edges. With x2, it would require 6 screenshots to completely cover the surface. On L maps, it's 4 screenshots with x2, and still 2 screenshots with x1. I understand that the scale may differ for different players due to different monitor resolutions and HD mod launcher settings.
I also have 1920x1080, and the settings in HD are default (1180x664). Do you have different settings, or are there other factors that affect the scale?
I specifically have a 1920x1080 monitor and a 1920x1080 setting in HD. Anyone using other resolutions needs to take screenshots, stitch them together (it's convenient to stitch 2 layers, if you make one of the layers semi-transparent, overlay it on the other, and then remove the transparency), and then adjust my grid to the edges of the stitched result. After that, the grid should be saved separately so that it doesn't need to be adjusted every time.
If all of this is completely unclear how to do it, I can record a short video of how I do it in paint.net
