Hi there!

Before addressing your two questions I did want to point out that the New Recording trigger currently doesn’t provide a download URL, which means that the rest of the workflow is moot (unfortunately). Adding that option is something other users have asked for so I've gone ahead and added your vote for this feature request. 

Zoom owns and updates that integration so it may be worth it to reach out to them and let them know you'd like to have that feature added :)

They do have access to the feature requests in our system but it always helps if they hear directly from their users as well.

For the sake of addressing your original questions:

1. As far as I know, you’ll need to have each user whose recordings you want connect their account in Zapier.
2. Yes, you could add conditions in a few different ways: lookup table (part of our Formatter app), Paths, multiple Zaps each with their own filter

Within Zoom, each user can set the folder that they want the recording to be saved into.  If that folder was a folder in your Google drive or dropbox, that you have installed on your PC, the record is converted after the meeting and stored locally.  However it is a pseudo local drive so it gets sync’d to your cloud storage.  If you have the permissions set on the folder so everyone can see the recording that works.

I will give you an example.
My company resells Keap and Infusionsoft.  We provide Zoom screen share training ans support.  Each of the coaches creates a folder for a client in dropbox and pastes the url of that folder into the CRM record.  After a session the zoom recording is converted and saved into the main folder.  The coach then just drags it into the clients folder.  The native sync happens and the new recording is in the client folder.  The same folder that the CRM has as a link that goes in emails to the client.

Not 100% automated but pretty effective for us.