I still get this error when using the JL-OneWorld method - I just gave up on it and use Awards/Oneworld or the JAL site directly.

It seems that KVS under Crossover is something of a lost cause - they certainly don't provide any support. I licenced KVS when the US/AA merger was announced as all OneWorld airlines are very difficult to search using a single tool - for *A I use both ANA and ExpertFlyer. Now with the US/AA merger delayed - my requirement of KVS is not as great - but this will change (I presume) - I will look into various alternatives - whether using VirtualBox / Windows for KVS (as suggested) or another tool.