I am designing a dual layer PCB and want to have copper area for grounding. As a result, I want to have as many tracks on the top layer as possible. Probably, for my circuit, it is not possible for all tracks (except grounding) to be on the top layer. The auto router ran for a long time and the maximum percentage in the progress bar is 96%. I am happy to have the remaining 4% on the bottom layer. So I stopped the auto router. On the PCB layout page, the routing on the top layer seems to be OK. Then I tried to continue the remaining tracks manually. It did not succeed. The tracks did not appear, instead a number of yellow X were created. Is there a way to 1 Request the router to lay as much tracks as possible on one layer and the remaining on the other layers? 2 Let the auto router to complete most of the tracks and manually finish with the rest. Meanwhile, I am trying to record those incomplete tracks, exclude it from the auto routing, route again and then finish it manually. But it is messy and error prone.