There are two reg paths for two kinds of rule:

1.HKEY_LOCAL_MACHINE\SOFTWARE\PSMFirewall\Rules
which is for IP/Port rules
rule sample: 

211.041.046.077|211.041.046.077|00021|00021|0|0
From IP|To IP| From Port|To Port|Reserved|Permit or not

Ip format: xxx.xxx.xxx.xxx
Port Format: xxxxx
Permit or not=1 or 0
Reserved always=0

2.HKEY_LOCAL_MACHINE\SOFTWARE\PSMFirewall\Rules1
which is for App path rules
rule sample: 
D:\Program Files\MSN Messenger\MsnMsgr.Exe|1
App Path|Permit or not
App Path=full path
Permit or not=1 or 0