When adjusting the GRID column margins I use the up/down arrow keys to adjust the number. This works real good until the left and right margins become uneven (due to the gutter with and number of columns) and four text fields show up (top, right, bottom, left). At that point my focus jumps to the artboard and I'm still pressing up or down, moving the artboard. I would like to see the focus stay in that area, if not still on one of the left or right textboxes.
Adobe XD 22.214.171.124
Thanks for reporting bugs!
As a workaround, you can use Shift+up/down arrows to adjust size in natural increments so that right/left margins do not become uneven.
Hope this helps,