since some of the functoins like proxy does not work properly for me in 2.5.1
EFW's Proxy/VPN/Firewall/etc., almost all the things are working and till now I know only one bug.
root@wiper:~ # traceroute www.google.com
traceroute: Warning: www.google.com has multiple addresses; using 173.194.67.104
bind: Invalid argument
Secondly, finding older version is difficult, may be someone over here can provide you if he is still using it.