tell your friend with 908 to upgrade to newest available version
tell your friend with ssl error to redownload full package from
https://oss.azurewebsites.net becuase it contains correct .dll files that must be used with that version of FlashFXP
as for passive error, without seeing exact status log and knowing more about network setup of that user, the only thing i can suggest they try is to disable pasv mode, and to try to connect like that.