About UPnP. I do use the same Mac (Modem and router) as with LW 4.9.33 which was connected very quickly. It means that modem and router was able (and still should be able )
I found somewhere in LW Forums a basic infos/request you made for a better help in case of trouble. Here is it:

1. OS version: OS X 10.3.9 (iMac 1.25Ghz)
2. What firewalls you have? ...?... Integrate to OS ?
3. How much ram: 768 MB DDR SDRAM
4. Hard Disk space available: 35Gb (80Gb)
5. Connection type: Built-in Ethernet, Modem Dash2,
Router 192.168.222.1(BLACKHOLE-1.IANA.ORG,BLACKHOLE-2.IANA.ORG)details
7. Where are you trying to connect from ? Yogyakarta/Indonesia
8. What version of LimeWire (LW) & Java do you have? LW 4.12.6 Pro, Java 1.4.2_12
9. Who is your ISP ? 35.subnet209.astinet.telkom.net.id
10. Test at: http://www3.limewire.com:6346/ What happens when you go there? 'Your test worked!'
11. Are you sharing the connection with other computers or p2p sharing programs?: No
12. Is this a your 1st try at LW or is this a new problem with an experienced user. New, after update from LW 4.9.33
13. Do you see a brick wall in front of the blue world icon at the bottom of LW's interface? Yes
14. Are you port forwarding or is UPnP enabled? UPnP enabled
15. What security programs are you using (antivirus etc)?: Only Firewall install in OS X
16. What country are you living in? ) Indonesia.

NewMacSharingFirewall


NewLWFirewallConfig


I wish It could help to find what is wrong... Am becoming mad !