Ideally Oak or other Hardwood planed to 7.5mm - 7mm thickness
Shaper with 1/8" bit
I have tried to confirm tolerances but even the Kapex Supplimental manual has about a 1mm of tolerance to my Kapex. But most should be able to dial this in with the screws leading the way.
I did the bore for sholder of screw to .15" depth about 5mm.
1) Mill center holes
2) Mill counterbore holes
3) Mill outside profile
I have added a SLOT version of the design. It is better at accomidating the largest tolernace it seems which is the width and is as closest to the intent of Festool engineering.
If anyone wants the Fusion360 file to tweak dimensions for your own saw let me know.