
Another thing that MAY help is incresing the ammount of ram your computer gives HnH.
Your run.bat file try this:
start javaw -xms512m -xmx1024m -jar haven.jar moltke.seatribe.se -r ./res
some other alternatives to try might be for 64 bit java/windows:
"C:\Program Files\Java\jre6\bin\java.exe" -Xms256m -Xmx512m -jar haven.jar moltke.seatribe.se
"C:\Program Files\Java\jre6\bin\java.exe" -Xms512m -Xmx1024m -jar haven.jar moltke.seatribe.se
"C:\Program Files\Java\jre6\bin\javaw.exe" -Xms256m -Xmx512m -jar haven.jar moltke.seatribe.se
"C:\Program Files\Java\jre6\bin\javaw.exe" -Xms512m -Xmx1024m -jar haven.jar moltke.seatribe.se
for 32 bit, just change the file path to: "C:\Program Files (x86)\Java\jre6\bin\javaw.exe" or "C:\Program Files (x86)\Java\jre6\bin\java.exe"
This is assuming you installed java to your C drive

To explain a little the part of the batch file that says "-Xms256m -Xmx512m" is the part allocating RAM, the first part "Xmx256m" is telling your PC how much it should allocate on start up of the application and "-Xmx512m" is the maximum, I'm pretty sure anyways, feel free for anyone to correct me if they know

Not sure if this will help much, I honestly don't know how to fix your problem but hey it's worth a try. Let me know if anything isn't clear

EDIT:
It may also be worthy to include the auto update in your haven client, you would need to edit your bat file and also put the updater into the haven directory:
batch file should read(roughly):
.\updater\HnH_updater.exe
"C:\Program Files\Java\jre6\bin\java.exe" -Xms256m -Xmx512m -jar haven.jar moltke.seatribe.se
Updater is here: dl.dropbox.com/u/18779594/HnH/HnH_Updater.7z