it may be too simple to fix it, but have you tried "entity_set_string" instead of "Entity_Set_String" (etc) ?
edit: solved a whole load of your errors includeing the capitalized letters that should not have been and a few natives that were incorrect, mispelled or incomplete in some manner.
a few undefined symbols left that I dont have time to look up.....
"CreateEntity", "FindEntity".... I cant remember the rest its not in front of me know, but compile this and you will see what is left to do.