Managed to get map time counter in lona status screen.
Edited this file:
LonaRPG\Data\Scripts\Frames\173_menu_01mainstats.rb
Added this line:
bmp.draw_text(157+8,12+85 ,160,60, "TIME : #{$story_stats["OverMapEvent_DateCount"]}",0)
I'm not sure if this is stable, I got one "file didn't load" messagebox error soon after I did this. But other than that, it seems to work.