hi, gal
are you wanting help on building the timer itself?
if so, the below post has a resolved question on displaying a timer, using a timer widget from marketplace:
https://community.mendix.com/link/space/widgets/questions/113331
Hey Gal,
Taking a look at your microflow it looks like you may need to refresh your client based on the changes made here. You could also look at switching the microflow into a nanoflow, which should make updating the client a lot easier.
Hope this helps,
Austin