I noticed this problem pretty early in the map making process. I'm testing out the map making process to find any kinks in the process before working on a really complex map (so don't judge on the map itself).
My idea as to the problem is the scale in inkscape. My scale is like 3.5x3.5 or something, however, it has to be that way in order to get the height and width to match the dimensions. If this doesn't happen the map appears really small in the top left corner. I can't figure out how to get my scale back to 1x1 without this happening (when it was 1x1 I didn't have this issue https://www.warzone.com/SinglePlayer?PreviewMap=75965
is the map with the 1x1 scale but incorrect dimensions as a result). I'll be able to add more detail after work.