help to understand making process

[Willy Tschager]

i have two question:
first: in prmiitive mode with a disc selected if i put in view preference
Move Snap  = 1 (1/1000 LDU)
Rotate Snap = 1 degree
i dont have any change.

"Move Snap" and "Rotate Snap" define the grid of the movements/rotations. Try using 1 for "Move Snap" and move your prim. Now set it to 1000 and repeat. You will see that you cannot make fine adjustments with a 1000 setting. You have to hit "Enter" after you changed the grid for the setting to become active. The same goes for the rotation. Try rotating with 1 and 90 degree. 

second: CSG seem dont make something if vertex is the vertex of the prim and the triangle are the mesh triangle. i think a make some mistake.

* Primitive Mode
* Select [1]
* Select the triangle from the mesh
* Hold down the STRG key
* Select the triangle of the ungrouped prim
* Both triangles change color from white to red. If one of the lines at the crossing of the hypothetical vertex is still white, something is wrong and you have to select again.
* "CSG Intersection points"

   

Theses are the triangles which must be selected. In your screenshot the triangle of the mesh is selected, the one of the prim is not.

w.