Kinda the same concept.
+on "tap" pressed
(sub event) +value "tap timer" is lower or equal to 0
-set value "tap timer" to 30
(sub event) +value "tap timer" is greater than 0
-add your double tap actions here
+value "tap timer" is greater than 0
-subtract 60*timedelta from value "tap timer"
...or something like that.
I have the same problem, but my question is, is "tap" the key being tapped?