Mobile scheduler add event

How can I programatically set the start date of an event?
The main idea is to click on the day view, and based on the click position I can calculate the hour, but how can I set it when the new event window shows?

I tried setting the text directly from javascript, but that does not seem to work(i can see the corect hour/day, exactly in the format used when I select an end date, but when I save it, a different hour appears)

You can customize new_event_data template:

http://docs.webix.com/mobile_calendar__calendar_templates.html#new_event_data