I followed your advice, then tried reinstalling Java and LW again (several versions)...No luck!

I always get the error described above after clicking 'Next' at the Firewall Preparation window. (I don't have a firewall.)

Do you know exactly what LW does at this point? How does it contact the network?

I assume the problem lies with my Internet/network settings...
The ADSL connection software my ISP uses (EnterNet 300 P.P.P.o.E. )seems to be a bit buggy and needed some tweaking to work properly...