Task list macro bug

Reported by Jonas Björnerst on email:

Hello,

I really like the tasklist macro. There is a minor bug however, that I
have tested in the TEST space at confluence.atlassian.com. Doing a
preview on a newly created (unsaved) page results in:

Error rendering macro: null

After saving, previews render correctly however. It would also be nice
if links worked in a tasklist. Now they are rendered as text with square
brackets.

Jonas