saguaros Hi,
The issue is no longer the configuration of NSP GK5, the root cause was found to be the VM Orders, when placing an order in the website, all of the NSP modules are messed up, instead of showing those 3 products assigned to the chosen categories, they are showing all products even those that are not assigned to any Category in VM.
The issue is related to the module Cache, since even after the user order, if you change the browser or delete the site's cash, the module's display is back to normal.
To sort this out and as per Joshua's recommendation, the module's cash has been disabled and set to 0, but the problem still persists.
Thank you for taking time to look at it.