AU$18m was for the European rights, as an ordinary shareholder buying CXS at 69c you are paying $195m + options dilution (>10x as much) for the US rights plus a potential 10-15% royalty on European sales...as a rule of thumb Europe is about 50% size of the US market.
IMO the numbers still do stack up and it will be interesting to see if RBS Morgans etc...revisit their sales projections.
Rgds
Prof