Miter structural members using 3Skeng steelwork

[newsketcha]

HI all.
I am new to this forum and even newer to sketch or any Autocad program for that matter. I am a welder and would like to use sketch up + 3Skeng steelwork to do my own drawings for home projects and the like.

My first question is; When I am using skewing steel work to draw a simple square frame I can only chamfer (miter) one end of each member, so say it want to make a 90deg angle I need two steel pieces cut at a 45deg cut back, on both ends as so the other member also cut at a 45deg can butt up to each other and create 90deg angle. I would really like to know how this is applied to my 3skeng steelwork.

Second question is much the same as the first but is for notching W and S ( i beams and columns) as so when the two are running at 90deg to each other one fits inside of the other until touching the internal web and also acts as a guest using 3skeng when you butt two members together there is no option for the join profile of the structurer.

Any help would be great thank you very much