I've looked into an app like this in the past. It is a daunting enough task with standardized containers and very accurate ship dimensions. Add in non uniform packaging, optimal loading sequences and port loading schedules and you have 1 whale of a project.
I have written some fairly simple storage capcity model routines in the past and really thought I would go nuts before they was completed.
I would have thought that there were some apps out there already that were up to the task. Very high dollar stuff I would guess. -David