When you run the server you will not be returned to the prompt, if this is a problem you can use the program screen to put it in the background or at the end of the command you are running to start the server put a "&" to start it in the background.
For example:
Speaking of commands, what command are you using to start the server? By default the server will only allow the localhost (connections from the machine running the server) to connect to it. If you want any machine on your network to be able to connect to the server you will have to tell it to listen on all interfaces by using the following command:
tiddlywiki . --server 8080 $:/core/save/all text/plain text/html "" "" 0.0.0.0
This will start the TiddlyWiki NodeJS server in the current directory, on port 8080, will display all tiddlers, ..., ..., will not need a username, nor a password, and will listen for connections on all interfaces.