@khn - I believe there are two requirements here:
- Restrict asset folder path in pathfield
- Disable date picker to go in past from today
Restrict asset folder path in pathfield: There is no property to restrict but there is a property called ‘rootPath’ to add a root path so other paths will be restricted. If this is doesn’t work then you can add custom JS validations in the pathfield to give an error if author selects paths from a restricted folder and the dialog wouldn’t get saved.
Read here for pathfield documentation and validation - https://developer.adobe.com/experience-manager/reference-materials/6-5/granite-ui/api/jcr_root/libs/granite/ui/components/coral/foundation/form/pathfield/index.html
Disable date picker to go in past from today: You can simply use property minDate as today and the datepicker will not allow to go in past. One drawback here is on selecting the date from datepicker, you can still select a date in past if you edit in the input field. Again, to restrict this you can add custom JS. See this thread/solution