Due to Highrise API restrictions, we can only export "open" Tasks which are visible to the current user and related to either a person, a company, a case, or a deal. If you need all of your tasks to be migrated, please send us a message to review the possibilities.
Private Tasks can be migrated but requires customization to do so.
Attachments can be exported, but only from emails and notes
"Remember the date" for Contacts is not supported at this time