I've been playing around with View Range a few days now. Trying to really understand how it all works with regards to Categories, Linestyles above and below, Overrides, and then the actual family settings. You don't realize how much more there is to it, other than just inputting a Cut Plane Offset, etc. 
Anyway, I've noticed something with Casework and I wonder why it is happening. I have created a basic Level Hosted Upper Casework Unit (not wall hosted), and have modeled everything at the Ref. Level (see image).
I then load this into a project and assign an 'Offset' to the built in offset parameter of say 1400, then I assign the Cut Plane to 1600, which would essentially cut through the casework, but it still shows the overhead lines (see image).
However when I introduce an 'Offset from Ref. Level' parameter to the family, the visibility acts differently.
I made the parameter (see image).
When this is loaded in, then I then apply a value of 1400 to the newly created 'Offset from Ref. Level' instance parameter and make sure the existing built in parameter for 'Offset' is set to 0. The elements now show cut.
Why is it that it only shows cut when this new parameter is assigned and does not show when you use the built in Offset. I don't want to have 2 offset parameters as this would confuse people. Same family and same project with nothing changed between either of them. I just added the one parameter in the family and reloaded it into the project and overwrote the existing without changing any settings.
