Admin Anywhere give you the the option to modify any product or category's directly from main site.
All you need to do is to log-in to your admin page when you go back to main page refresh and you will see the icon link that allow you to modify the product in the main website.

Support only VQMOD (upload xml file and you ready to go).
If needed file modification it can be sent to you after purchase on a special request with additional charge.

I believe the the core file should stay untouched. This way you will not get errors.

YouTube demo : http://youtu.be/wog601RLI-U
http://opencartil.co.il

Updates:
22/09/2014
Compatible with 1.5.6.4
Add New Edit option to Sitemap

Updates:
23/03/2014
Compatible with 1.5.6.1

Updates:
14/11/2012
Add to Manufacturer page.

Update
24/11/2013
Test Module On 1.5.5.5
Working OK