The map file riverside_under is missing a down ladder at coordinates 1,20 - as this is missing you are unable to go down further to a lower level to work your way back up to retrieve Esmeralda the goose to give back to the coffee shop owner to get the coffee to get the port pass.
Down ladder should be placed at 1,20 riverside_under and the destination 19,19 riverside_under
Corrected map file attached
I am working on this issue.
Patch accepted and applied. Thank you for working on this issue.
https://sourceforge.net/p/crossfire/crossfire-maps/ci/420e3dad68c97aaa655d1f8857f017d762604749/