I think there's a bug with the dimensions. No consistent values given.

Why is this happening? Last measure should be 121 but it's 120.99

It is the Snap to entity function... the snapping isn't 100% accurate. I'm opening the issue later

That's the problem. I don't know if this is an intended behavior: when you use the move command, if you hold down the shift key to get the horizontal or vertical constraint, when your selection is already snapping to something, as you keep holding the shift key, the mouse up and down movements will slightly move the selection to the left or right.

Should I open the issue on github?