When you use C-shape channels in your assembly, they don't look like channels in the drawing because channels have a series of tangent edges to make the rounded flange. Turning on tangent lines often clutters the drawing too much. I propose that there is a toggle for "simplified structural steel representation" to make the nominal flange thickness be a single line instead of several tangent lines. See attached photo (I hope it works, because I've been having bad luck attaching on this new revision of the website...what happened to the "insert image" option?).