Reports: Permission Denied - "Cost of Goods Sold" Extension

Alright....this has me stumped.
I'm using OC v1.5.6.4

I just installed the "Cost of Goods Sold" extension.
https://www.opencart.com/index.php?rout ... _id=572436

After install, the "cost" field has been successfully added to the product table in the dB and the "cost" field shows up on the product edit page in the admin panel. The problem is when I try to get to the report screen in order to run a report. I click Reports, then Sales, then "Cost of Goods" and when it tries to open the page for the report I get a "Permission Denied" error. All of my other report pages work fine. And I tried 755, then even 777 permissions on all files that were uploaded as part of the extension with no luck.

Let me know what other info to provide and if you have any ideas

thanks!

Go to "System->Users->User Groups" in the admin and edit the top-level admin user group. Make sure all boxes are checked in the access and modify lists.