Admittedly, this could be considered user error, but there was nothing that made it obvious in the UI that I needed to do something different.
When doing a material test (on some thin plywood) - it appears that it overrides primary speed/power settings for all the layers it uses, however - it does not change layer modes, or any sublayers. In my case, I happened to have run it after I had a project open, and one of the layers was a two-sublayer setup with a line and then a high powered fill (doing some TiO2 on tile) – and it was the layer the border was using in the test.
All went great until the test promptly proceeded to vaporize the entire block of material line by line as it completely filled in the entire border.
It seems like the material test should either make it very clear in the UI that you should start from an empty project/no changes – or it should override ALL of the layer settings.
Note - this also had similar affect on C00 layer for the test squares and whether they were filled or not - though that one may be intentional/design.
1.6.03 on Win10 with a Falcon2-12W