Usually this is because the outline must be connected in the exactly continuous points. Use an appropriated grid to draw the board outline.
The start/end segments must be exact in the same coordinate point.
Please have a look at this issue:
Usually this is because the outline must be connected in the exactly continuous points. Use an appropriated grid to draw the board outline.
The start/end segments must be exact in the same coordinate point.
Please have a look at this issue: