Hi Rudl, it is possible to create a point object where a line and plane intersect by using the Construct > Curve > Isect command:
To do that, select both the plane and your line (it should be a regular line object and not a temporary "construction line"), and click that button and a point object will be generated at the intersection.
That command will generate curves where 2 surfaces or solids intersect one another, and also point objects where curves intersect other curves, surfaces, or solids.
> Is it also possible. to find out the point between a constructionline and a plane.
Not directly with the construction line itself, you need to draw in a regular line object which can then be selected and used as input into Construct > Curve > Isect.
> Is it possible to use constructionlines with points.
In what way? Do you mean while drawing a point object? Yes  you can use construction lines in any "drawing" command where MoI is asking you to pick a point location.
 Michael
