Branchline track plan

 Here is the plan, after moving the sawmill back to the corner.

With the corner harbour being part of the branchline, there should be a small yard located there. The mainline, in this plan has 4 westbound and 2 eastbound industries to be switched, plus a passing track in each direction. Probably the lead to the lumber yard should be facing the other way, which would even out the east and west switching.