As I recall seeing in this forum, there was a SQL patch file for Zen Cart itself related to one of the older versions of Zen Cart and it needed to be installed prior to this plug-in. That said, seeing that you are running 1.5.1, well I don't know of any SQL patches, but... there may be/the instruction still applies in general: make sure ZenCart is up-to-date prior to use for the version that you use.
Item 4 is about uploading the SQL file to support this plug-in as a new user. (Yes, until this is done, there may be errors that appear in the error log(s), because the data storage location may not exist to accept the data collected in the uploaded files. Another change I think to be made in the instructions (SQL before datafiles), although also thinking that installation could be improved through the use of an autoinstaller as well.
Clear it up any?
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