I posted this question yesterday in official wf-downloads forum, but still no answer... Hope anyone will know an answer here ;)

How could I change download permissions via MySQL database directly (by running sql command or changing some values)? What parameter in which table/field must be changed?

I want downloads to be accessible not only to admin/registered members, but to anonymous as well. And I can't use XOOPS Admin Panel to select downloads (which permissions I want to change), because my directory contains over 15.000 downloads and browser gets timeout (or stops responding) each time I'm trying to do it.

Any ideas are very very welcome

But you would change permissions through system admin to enable anon access. To change the catergary permissions, may be you can go directly to this page:
http://www.yoursite.com/modules/wfdownloads/admin/category.php

All the categories have anonymous access already, but downloads are not visible to anonymous users (they can browse categories, but categories are shown as empty for anonymous).