Yes, observe/control is designed to work from outside to things outside, and it uses the FileWave server as a hub.
Note in the first illustration of the client connections, there is a client to server 20030 Observe Data, and an admin to server 20030.
Make sure that connection is working.
Also be sure the observe is enabled on your clients by making a Superprefs file.
The issue you are seeing with client monitor not working has to do with connected IP vs current IP.
Remember Device Details are stored inventory information, client monitor is a direct admin to client connection (see that tcp first illustration again)
Lets say you have a computer on an internal network (Ip 192.168.1.100) but your server is hosted and sees the client connection coming from the NAT IP (188.8.131.52).
When you select a client in admin, and choose client monitor, I'm guessing it is auto-filling that NAT address that the server sees the client coming from.
You will see the current IP in the client info window > device details. Entering that into the client monitor should allow you to connect to the client directly (given that you are on the same network as them, and that 20010 port is open between you and the client).
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