1. sling load assault boat to Huron via scripting command
2. set "drop cargo" waypoint for Huron
3. test it in editor/sp/mp with one client/mp with more then one client
(no dedicated server was used)
my results:
editor - working
sp - working
mp with one client - working
mp with more then one client - not working, helicopter goes down and boat touches water but is still sling loaded
see the attached mission