You can use the same filters in Surveyor as you have in Content Manager.
So:
Payware = False
Now it could be that you have payware installed from 3rd party sites. That content is not flagged as Payware but instead will be flagged as locally modified. So if you want to exclude external content (both payware and freeware and as such save future appreciators a KUID hunt), make the filter like this:
Payware = False
Locally modified = False
... but that would also exclude your own made content, so if you want to keep that in, add:
And Not
Author = #self
... but current built-in content might not be uploaded to the DLS for a long time after the next version of the game is released, so you could also consider adding:
And Not
Built-in = True
You can save filters in Surveyor, so save it as "No payware" filter or something like that.