Can I change the date format to Swedish standard?

My second question: the time format (e.g. 23-10-2017) is not according to Swedish standard, which would have been 2017-10-23. Is there any way of changing the format?

The submission date/time is hard coded and cannot be changed.  You could integrate your form with a Google Docs spreadsheet and apply the correct date formatting in the sheet:

https://www.jotform.com/help/228-How-to-Integrate-Form-with-Google-Spreadsheet