The OP is not trying to create slots , the fab is telling him he has invalid slots: bingo, you 're right, i don't need slots, not panellised pcbs by exemple.
1) a design is created using an older version of KiCad. That version has footprints that have oval holes. Since you can't drill an oval hole, KiCad simply output a drill instruction to the Gerber. Gerbers are sent to the fab, fab and user are happy
Yes, i use an old version of kicad, 4.0.4, but first i set pad properties for SCR and BCxxx to oval, and same length for x and y.
Changed lenghts o different values, after.
Result: Slot missing said by manufacturer board.
2) user upgrades to newer version of KiCad, but doesn't change footprints. New KiCad now outputs G85 for oval holes, fab and user unhappy
I'm still unhappy - bad beginning of this year ::::::::::::::::::::)))))))))))))) - but not upgrade to newer version.
3) KiCad Librarians realise that oval holes in footprints are causing problems, and change all holes to circular.
So, i'm going to change oval to round and same x and y lenght, for footprints and pad properties too.
Going to 4.0.7.