Vdave

The reason you are getting the deflection failures for the pitched portal is that, STAAD.Pro is connecting the nodes DJ1 and DJ2 by a straight line and calculating the deflections of the pitched member with respect to that line. You should not check deflections…

I ran your model in version 20.07.10.64 and members 1308 and 1310 are failing in slenderness with utilization ratio 1.1335. So it seems that this issue is fixed in the current STAAD.Pro version as I noted previously.