Get NDI Tools, and NDI Access Manager in particular.
On the sender, start Access Manager and enable Multicast Sending.
Now start Resolume on the sender, and start your receivers on the network, and it should 'just work'.
Of course your switch and devices need to support multicast too.
This is all managed by the NDI libraries, Resolume just tells the library the texture to broadcast. So if you experience issues, it's best to contact Newtek about them.
Improper configuration can bring your network down, so be careful.