I've setup a new store using zen-cart 1.5.1 and we've CSVs to add products / categories / manufacturers, we are using Easy Populate and it works great, unfortunately, I didn't find any option to manage attributes, we've a huge set of attributes per product and attributes vary significantly.
I bought Magnetic One Store and tested, it does not support attribute export / import. So it's out.
Advance Easy Populate says that it is compatible upto 1.3.9h Check here
is not responding to my sign-up request and not sending the details.
So, I'm stuck and looking for experts opinion here on how to import / export attributes?