Hi Guys
Thanks for your feedback and welcome to the forums Frank.
I will make sure a slope video is completed. We are actually going to spend a while producing more videos for the 2017 release however we are working on the website upgrade at the moment which will have a special area for learning materials with all the videos. With the slope element you are defining a perimeter for the slope as well as three points in space which define the plane of the slope.
It is quite confusing and we have a work item to give another option in the 'Define' drop down which allows you to select : Arrow, Three Points, Arrow & Offset, Three Points & Offset. The arrow will take a height at its base and then a direction and angle. I think for a lot of people this is a more intuitive way to define a slope.
One tip I would give is if you have defined your slope perimeter you will probably know what height at least three points are on that perimeter. Move the three points to those positions and then set the heights. I find this a lot easier to understand than setting the points randomly in space.
Definitely worth checking the surface in 3D to make sure it looks right.
-Ted
