I'll just take the last part. We used to buy treads , and make treads only for the pickiest people. Even the bought ones had to
be jointed and ripped to size. Then we ran the front edge "bull nose" on the shaper. The best looking grain always went toward bullnose edge. And the best looking treads were always toward the
bottom of staircase. Treads got a 1/4 " tongue" cut on the shaper The risers we usually made from oak bought un dressed ,we used dados to cut 5/16th wide and deep dados , fine grain went
to riser top. Treads were not glued to risers, we drilled holes thru riser and and little way into tread, and then nailed
risers to treads with headed ,coated nails. The nails at the ends were always about 7 or 8 inches from ends. There is a good reason for that. No
matter how accurately you lay out your marks for routing the stringers things are never perfect. So when wedging up the
stair if you have any tread noses that that won't seat property ,you can bop them with a rubber mallet and the un-
nailed tread can go into place by "leaving the riser behind".