Here some i made http://www.mediafire.com/?zsbg7wkb2ru39w0
mirror: http://www.easy-share.com/1912131965/operation arrowhead DEMO mission pack.rar
http://uploading.com/files/566b6c65/operation%2Barrowhead%2BDEMO%2Bmission%2Bpack.rar
extract in your ArmA 2 Operation Arrowhead DEMO folder
You can
adjust the number of forces group the allies whit the team leader and syncronize them whit the module
add several more enemy squads and then change their Probability of presence
move the mission to another town you can drag and select units and waypoints
edit:
DEDICATED SERVER
create a shortcut of ArmA2OA_Demo.exe
right click and select properties
add the following at the end of the target
-server -config=server.cfg -cfg=basic.cfg
hope to see some ppl hosting them
have fun :D
edit 2:
also made this 4v4 maps pack http://www.mediafire.com/?whdyb36gfilf3hr