Good to see someone else trying to bring a stack of machines into the fold
The shortened version is the first answer on
this thread.
Then I suggest you read the pages from
the project FAQ on FaHWiki under the header "what about security". Some of the links are out of date but all the information is still relevant.
If you only get your clients from the download page, then there are no leakages possible in terms of security unless someone can modify packets in transit across the internet, which is a problem if you're browsing google or using F@H lol...
To protect against modified packets all data transferred across the internet by the client has a 2048-bit key on the end, and if the checksums don't match at both ends then the data is discarded whether it is coming to the client or leaving from the client.