Stefan, can you please define what is a "local" network?
The Agent work with the SMP. When in the same network as SMP, it will be able to download packages. If moved to the other network, where SMP is not reachable, then no package download will be available any way, since every package download want to receive the package information from SMP.
Using CEM alows agents to connect to the SMP through the gateway, so package download is also possible. Future release will contain the check-box (mentioned earlier) to turn-off p2p when CEM mode is active.