Yes. In order to do a flashing effect using the PICT command you need a blank card. Also, since you cant put TIMERs within TIMERs you have to use a loop script. This is how I would cause the flashing effect. just so you know this flashing effect would be permanent until you go to a different card.
(lets use 25 as our blank card and 20 as our current card)
"Loop Script ON"
IF x = 0 THEN
x = 2
ON TIMER 10
x = 1
PICT 20
END TIMER
END IF
IF x = 1 THEN
x = 2
ON TIMER 10
x = 0
PICT 25
END TIMER
END IF
If you need to put other stuff in the card script you can
IF y = 0 THEN
y = 1
'all my cool commands and stuff'
END IF