Import/export function just spoiled the whole game. There's now an easy way to get all the money you want. So what's the point in progressing? Also the cap for minion amount is silly.
Boring as hell. 20 clicks to close dumb and meaningless dialogs. 30 seconds of shooting. Repeat. Only way to die is probably standing and doing absolutely nothing, yet even then you have automatic gun that shoots at zombies. Graphics are nice, nothing else.
If anyone's wondering why there's a cap at 9,2*10^18 - amount of money is held in 8 byte (64-bit) memory address, otherwise called "Quad Word". This is the largest Hexadecimal number built-in Windows. The highest maximum value for 8 byte digit is 18,446,744,073,709,551,615. If it's unsigned, then you get values ranging from -9,2*10^18 to 9,2*10^18. It's probably also a flash limitation. Doubling cap value would only give you one upgrade, but it would probably take too much work to go around this limit.