Thanks for sharing that, sometimes there can be one or two little adjustments that can help things along.
The only thing that sticks out to me would be to change the layer height to .2 instead of .3 and maybe turn the temperature down to 190-200 but if you’ve printed other Clorehaven tiles with this then it shouldn’t matter. Could be worth a try though.
I downloaded the schist walls and put them through Cura Slicer to ensure there weren’t any errors with the file and it looks good.
To be sure I ran a repair script through Netfabb and it’s not showing any errors either.
You could try using Cura as the slicer for this and see if it prints correctly, that’s what we use for most of our prints and haven’t had any issues with the schist walls.
Hope that helps and gives you some options to try out.