Setting the repeat end date only works if you click on the date in the JS date picker. Entering it manually doesn't throw an error but also doesn't change anything.
Thanks for spotting this. Actually the problem applies to all datepickers, not just the repeat end date. Fixed in Rev 2804.
You seem to have CSS turned off.
Please don't fill out this field.
Perfect, just tested it and it works as expected now. Thank you!