AlterBrains

I think this may be what we need, but I am just checking. We want to use one file manager system and organize and control the files in one master joomla install, but let the 4 other branded sites pull from that info. Is this the component that we would use to do this?

thinking of using docman or dropfiles.

Yes, exactly, MightySites allows to run multiple Joomla websites from single installation of Joomla on master site.

Slave sites are created as parked domains in hosting panel - so they use same files.
But each site can use own database tables and hence have own contents.

ok so the slave sites can be a fully functional existing Joomla install, and we can use mightysites to share the download manager from a master site. So we don't have to worry about changing the existing site's setup or anything.

Download manager should use native Joomla database layer.

Please advice more details about existing sites, are they already using same server folder?

same server all on the same directory level, different databases. we are using a special authentication since we are being pushed users via csv files. But I don't believe that will play into the use of the download manager.

OK, so it should work, please choose preferred case study first:
http://alterbrains.com/joomla-extension ... se-studies