Thank you for your post.
There are two ways that this can be resolved, which I've explained below.
1. When you're drawing the skillion roof use the Ctrl key (for Windows) or Command (for Mac) to toggle the eave overhang. This will toggle the overhang to either be 0 (the roof will line up with the pitching point) or the measurement that's entered in the dialog.
2. After the skillion roof has been drawn, manually edit the geometry of the roof with native SketchUp tools to get your desired result.
Would you be able to please let me know if these work for you?