Probably. But if you don't run into too much trouble I would leave it running. - (You know that OSX comes with it's own integrated iptables based firewall?)

No matter if you use Basic or Pro, the program itself stays the same. By buying LimeWire Pro you can support LimeWire's efforts to improve the client.

"Monitor" will just show incoming searches. Personally, I find it a little dull to look at other people's searches. In the same window you will find the upload screen, showing all current uploads.

The "Connections" tab will show you what ultrapeers you are connected to. Not necessarily very useful for the inexperienced user (and not really useful for the expert either).

No you are just seeing what other people are looking for.

You should only see three hosts. LimeWire rarely creates 15 outgoing connections for some reason, that's a still unidentified bug. Those connections are the ultrapeers you are connected to. If you are an ultrapeer yourself you will connect to more ultrapeers but also to leafs who will search the gnutella network through you. The ultrapeers are a little like servers that send your searches to the rest of the network.

You cannot restrict access to a folder with a firewall. You can only restrict access to certain network ports but that's not necessary if no application is using the port or if the application using it should have unlimited access to the network.

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