Both are pretty simple to questions.
1) Orienting fixtures:
With the fixture selected, in the OIP scroll the "Set 3D orientation", check the box, and set it up. It's easiest to be in a 3D view for this.
2) Drawing pipe:
I draw a circle, 24mm diameter, and then extrude (cmd+e) to the length I want, i.e. 1000mm etc. Then I go to the front view and rotate (cmd+L) to get it to horizontal position.