Q. I am creating a counter top with a built in drain board. Is there a way to create a tool path on a slope so that the water can drain?
A. Yes, it is called Edit Z Point by Point. This command will be used after the geometries have been created and the proper tool paths have been applied in a 2D orientation.
2D Geometries have been drawn and tool paths applied with proper Z depths seen below.

After running a solid simulation with the above results, note that the drain area is currently at the same Z depth seen below.

Activate the Edit Machining/Edit Z Point by Point command from the Machine drop down menu.

After activating the command, the prompt bar at the bottom of the screen requires a tool path to be selected that will be used to edit the Z points.

After selecting the tool path, notice the start and end point nodes that are visible as seen below.

Either one of these nodes can be selected or you can manually enter the X.Y, coordinates of the location to edit the Z point of the tool path. In this example, the far left or start point node will be selected.
After selecting the start point node, the prompt bar will show the current Z value that was used when creating the tool path for this location.

Edit the value to be greater than the -.625 value used.

Select OK.
Notice in a wire frame, 3D view, how the tool path starts at one depth and gradually slopes to the original final depth of the tool path seen below.

Solid simulation view seen below, from above results.

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