I resolved this situation following the following process. After adding
the MySQL path to the environment, I kept invoking the program and then
checking Event Viewer in the Application Log for MySQL errors that
referenced old commands in the ini file. After removing them, what was
hanging me up was that the installer was looking for errmsg.sys in a folder
that didn't exist, inshare. Those folders DO exist, but on the same level,
not nested. So I added the folder share to bin and copied errmsg.sys from
share to the new nested share, and it worked.
Now that its running, I intend to redo a proper configuration using the
workbench, just to gets my ducks in a row.