I'm curious to know if you can possibly connect with any gnutella program. Possibly try GTK-Gnutella? Gtk-Gnutella - Browse Files at SourceForge.net

As for WS, perhaps you could try the earliest WS version: WireShare - Browse Files at SourceForge.net
which should not be dramatically different from LPE except in the way it's installed.

I use applescript installer without a post-flight script like the original LW/LPE does & which used a java based installer instead. Thus no Receipts registered by OSX for the installation. I would think this should not be an issue. But then I could be wrong when considering the way OSX is heading.

BTW I am wondering about your port forwarding. Did you enter the correct internal address of your MM computer? And not your iMac. This can be checked by checking your MM's system prefs > Network > ip address. And comparing it to your router's port forward rules & which address they are assigned to.
BTW a port forward rule can only apply to one application and only to one computer on the local network. And you cannot have two port forward rules using the same port.