While trying to tweak infill, there is a tiny bit of UI fail: there's a critical parameter (infill width/height) that is controlled by two or more other parameters, but is itself never actually shown to the user.
Getting this wrong has no effect until you try to print, at which point you are told it is wrong, but the value is still not revealed:
1- Please show the ratio on the appropriate tabs,
2- If possible: please highlight it when it's out of bounds,
3- If possible: please perform the validity check before letting me save/ok the profile.