Differential pair - Unable to tune skew/phase

When i set the differential pair gap lower then 0.18 mm i can’t tune the skew/phase (include track length). Tuning differential pair length works OK.

I checked the design rules and everything looks good.

kicad version: 53204e097 - x86_64

Any ideas?

And where i can find it?

dimensions -> differential pair.
Not sure if this exists in stable.

Nope, this is only the basic setup of differntial pair… There is no other options to change some limits?

I fear this is everything that exists in the current software. Maybe there are some specialized builds out there that have better support for such things. I think there is a RF build somewhere.