I worked on this at one point and found that running the same app on multiple versions of macOS and Windows resulted in different alignments in almost all cases. Apple certainly assumes that you’re using baseline constraints (which Xojo does not) and Windows… the only way I was ever able to get things right was to eyeball it.
It should be possible to create a method that you’d run on a window or container that would make th we adjustments for you, but it would have to be Xojo-version specific as they’ve made adjustments over the years.