Why my report is not displayed on the Issue Export panel?
Issue Export panel contains only scripted reports with chosen Issue Picker. To check, if a report contains Issue Picker you should follow the steps:
Open the report you miss in the dropdown and click on pencil icon.
Check if the selected report contains a field with Issue Picker type in Input fields.
Why can some reports be exported to PDF and attached to a task, while others cannot?
Some reports have multiple Input fields. Export to PDF and Attach to issue options are available for a report, if it has only one input field with Issue Picker type.
...