I’ve added datepicker to our list of desired features.
In the meantime, please do not try to use html form elements. I am 99% sure that no data from them will be saved. I had a similar issue with a student who added html hours and minutes to a PSQI survey on Qualtrics and therefore didn’t get any data for those sub scales.
In the meantime, you could use a Multiple-Choice Matrix (as I do with the PSQI).
Out of curiosity, how did you manage to get the text Start in the button upon opening your survey? Mine just says Next and I haven’t changed anything in the survey settings - I can see the option Start but it just doesn’t show in the 1st page of my survey