Here’s a version that’s a little more robust that will regenerate the card and allows for interactive updates to it:
# paste this into a card's (slide's) script (menu Card->Script...)
on view do
# boilerplate start
if card.widgets.sentinel
each k in keys card.widgets
card.remove[card.widgets[k]]
end
end
f: card.add["field" "sentinel"]
f.show: "none"
# boilerplate end
# your slide commands go here for each card
# this is different for each card (slide)
f: card.add["field" "title"]
f.pos: 30,30
f.text: "here is a title"
f.font: "menu"
f: card.add["field" "info"]
f.pos: 50,100
f.size: 200,200
f.text: "here is some information"
end