As mentioned, you don't need SBHost.
A quick search of the SB support forum
http://forums.avsim.com/dcboard.php?az=&forum=140
http://forums.avsim.com/dcboard.php?az==655&page=
States "Delete b5 re-install SB - if I remember correctly point it to FS2K2 but when prompted say it is FS2K. It should then install 2.3b4 "
I use 2 PCs to fly Vatsim without a problem but use the earlier version of SB (build 4) and Win98SE not XP.
In the hope that this will help I will do my best to explain how I have my set-up.
Install SB on the client PC (the one with Internet connection, where you have FSMeteo), not on the server PC.
Make sure it installs build 4 and not build 5, although I have heard that build 5 *does* work.
You then need to enter a line into the Windows\squawkbox.ini immediately after the {SB} heading; 'WIDESERVER=3'
You also need to rename the 'Aircraft.csl' file in FS\aircraft\ to 'Aircraft.cfg'
When you start SB and it asks for an IP address to search it seems there are 3 possible entries.
1) Leave it blank, and it should find your MP session (works on my set-up)
2) Enter the IP address of the PC running FS (probably 192.168.x.x)
3) A 'loop back' IP address 127.0.0.1
When SB runs you should see 'WideFS FS2K override active' in red text in the SB window.
I assume you have WideFS set up for TCP/IP, as shown in Pete's documents, otherwise I suspect Meteo and Flight Tracker would not work.
Hope this helps.
If not try a post on the SB support forum and give as much detail as you can on the actual error msg.
Rgds