I just did some work on the cargo collection system, so far I haven't had this issue with the new code; so, it should be getting fixed in tomorrow's release.
As others mentioned, the card-management UI is a disaster (take a look at Tyrant for good ideas).
The gameplay itself is fun, though almost all the missions are easily beaten using rush decks with high ratio of gold (and no other mines) - so I guess some rebalancing is in order.
Also, the enchantment used by the undead opponent is a stress test - last time I played Flash crashed after reaching a point with dozens of skeletons on both sides (and souls ~1000). I think it should create skeletons with lower probability.
 "Obliterate Everything 2"){kind=icon}
 "The Fall of Mr. Wily"){kind=icon}
 "Tourist Paradise"){kind=icon}
 "Battle without End"){kind=icon}
 "Castlewars"){kind=icon}
 "Enola: Prelude"){kind=icon}
 "Submachine 7: the Core"){kind=icon}
 "StarDust I: The Fall of Man"){kind=icon}
 "Discovery"){kind=icon}
 "Cardian"){kind=icon}
I just did some work on the cargo collection system, so far I haven't had this issue with the new code; so, it should be getting fixed in tomorrow's release.