Disappearing Font and a request

When I opened a slide show I created a couple of years ago - this week for no apparent reason, the font I had used has changed to a standard block font. The font I used is still in my computer and can be used in other apps but now it isn’t on the drop down list of fonts within FM. I also created this same slide show with the 3.8 version of FM for use on my laptop and it is stored side by side with the 4.5 version on this computer as well as on my laptop. I played both versions on this computer. The 3.8 version plays with the original font, the 4.5 version has imposed a replacement block font.
Why has this happened? Can I restore a font within FM? The font was Monotype corsova.

The request - As I am now having to edit in a new font on the 4.5 version, it would be especially helpful if there were grid lines (not the two yellow centering ones) to help position the text more accurately especiall when blending from one image to another. If not a grid then co-ordinates.
Another request - Helpful with editing - is it possible to store which font was used and its size. If I haven’t written it down, I have to go searching in the font book.