As the Xcarve is not “a rigid machine” there is some flex at play.
This equal, assuming bit diameters are true to spec, that inside cut parts (pockets) are a little on the short side and outside parts (inlays) are slightly oversized.
So, you need to learn the tolerances of your machine.
Fudge with the stated bit diameter to “cheat” a wider or narrower cut.
For inside cuts say the bit is less than actual and vice versa for outside path, go slow and incremental until you reach proper fit.
However, it might be better to use a V-bit for inlays as you have approaching walls between the pocket and inlay.