I have a footnote marker on one page, but the corresponding footnote appears on the next page. (Issue appears in the Noli me Tangere file I send to Mike Day on page 226-227)

Furthermore, I don't see to be able to insert space between the footnote label and the footnote.

The footnote is displayed on the next page because there isn't enough space to display it on the current page; the line with the footnote call occurs right at the bottom of the page. Another solution would be to move the line to the next page as well, but that's not always desirable either, so currently Prince just moves the footnote to the earliest available space where it can fit on the page.

Space can be added around the footnote marker at the bottom of the page by adding padding using the ::footnote-marker pseudo-element, like this:

.displayfootnote::footnote-marker {
    padding-right: 10pt
}

Mike is this still the current behavior for footnotes, to move to the next page if there isn't room instead of moving the text associated with the footnote?

And if this is the behavior when you are doing multiple column footnotes would you expect the footnote to be laced at the top of the next page.

If it is not I have a file I would like to post as a bug.

This is still the current behaviour, and footnotes are always placed at the bottom of pages, never at the top.