You need to make sure that you crossark is set up as a cluster, even if you only have one server in it. Then make sure none of the dino download/upload boxes are checked.
Make sure the same cluster code, for the main map, is saved on both maps. Then all the boxes need to be unchecked to download/upload characters, Dino's, and items
Yes before. Say you put your level 326 Argy in the OB with all your asc gear to head to SE, but you forgot to check the upload survivor box. If you go back and fix the setting to upload your survivor, you'd lose all of that stuff...take it from me.