Actually, thinking a little more about the long path-name problem, why not just cut out the middle part of a path-name that is too long and indicate that with an ellipsis. That way it would be clear whether something was on a storage card or not.
Example:
Full pathname:
\Storage Card\My Documents\Databases\Sample Database.cdb
Current rendering:
\Storage Card\My Documents\Data...
(Problem: Don't know which file.)
Last part of string would be:
...nts\Databases\Sample Database.cdb
(Problem: Can't see it's on a Storage Card.)
My proposal:
\Storage Car[...]ases\Sample Database.cdb