Warnings or errors?

[Dauphin]

After doing an analysis on the enclosed schematic (see below) with the EMS CAD software, I get the following warning:

[Tech2]

The CAD sees the slot as a hole due to the way you drew it. You can ignore the advisory in your case. Or you could recreate the slot from an adjacent view and use the Groove feature to create essentially the same shape.

If you point your mouse to the "Show only recommended materials" checkbox you will get a description of what that checkbox does. There is no problem using the material you selected.