Step 2: Right Click inside the building perimeter and choose the Edit Wing Attributes... menu item.
Step 3: Go To "Purlin Layout Style" and click as shown
Viewing in 3D you can see that the purlins are staggered and that the overlap is minimal. (While in 3D you can hit the 'W' keyboard button for the wireframe view.) The idea is that an overlap is set up so that there is slightly more purlin to attach to the top chord than a butt join.
Step 4: Go To "Purlin Layout Style" and this time also click the "Extended Overlap" Checkbox. Extended Overlap forces the purlins to overlap by about 1 foot either side of the top chord meeting point, as shown here:
Step 2: We are going to force the trusses to attach to posts, so locate the "Trusses Require Columns/Posts" Checkbox as shown:
Step 3: Next, locate the "Spacing Method" as shown:
Step 3: Look again at the main screen at the building outline; note that now, the sidewall posts show a distinct smaller bay on the right side.
And you can also see this reflected in the 3D view:
(You can get to this angle in 3D by using the 'U' and 'D' keys. In this screen
capture we used the 'D' key to rotate DOWN and then used the arrow keys and
PgUp/PgDn keys to move high and low.)