[DerekAsirvadem]

For 1.

Just pick up the bottom right corner of the window and drag it) standard Apple functionality).

If the stencil is drawn properly, it will have a default size, where the objects are rendered well. Very few are, especially now that we have every tom, dick and harry uploading ordinary diagrams as "stencils". So you need to look at the several stencils available for your need and pick out the better ones. Some "stencils" do stupid things, such as: fill your screen; object size inconsistencies; incorrect or no handles; absence of scaling; no grid orientation; etc. Any of which pose obstacles to using them, and define them as non-stencils.

Not sure, from your wording, but ... you do not have too copy all the objects in a stencil: just leave the stencil open, next to your doc, go to the stencil; pick up one object; drag it onto your canvas. And so on.