It seems to be the case that you
cannot edit or delete your
textual inputs yourself.
But if the problem is with
the picture then there is one way:
You can upload there a new picture with
the same name and it will appear there
at the board instead of the picture,
which had the same name.
But if your code pointing
to that picture is wrong,
you can't edit that yourself.
It is best to try first
always with 'preview'.
- Hannu