Hi @asmecher,
If memory serves for this one, the error message looked similar except that it referenced mysqli_connect() instead of mysql_connect(). At this point, from our other conversation (Issues installing OJS v3.2.1-1 - #13 by cbirmingham), I think we can move past the error and circle back to the initial questions regarding how a data import is likely to behave if the destination OJS config doesn’t match the source OJS config. For instance, are we likely to see any import problems if there is a difference in database name, or repository identifier?