Well, for "fun" - I took a look at the code... Here it is:
static const int64 MIN_TX_FEE = 100000000;
static const int64 MIN_RELAY_TX_FEE = MIN_TX_FEE;
static const int64 MAX_MONEY = 50000000000 * COIN; // 50 Billion supply.
inline bool MoneyRange(int64 nValue) { return (nValue >= 0 && nValue <= MAX_MONEY); }
So it is only a 50 Billion supply.
Don't know why the OP didn't check this...

Well, because honestly besides simple HTML I don't know code...I wouldn't know where to begin to look for the info you provided above.
I don't know why it is only a fixed 500 coins...
The dev is not available. He was simply paid for the code, and this is what it is. So...if any dev wants to pick up a coin...
I will fix what info I can, on the post and website, but beyond that, I am not a coder, so I am sorry. I wanted it to be a good launch, be part of a launch...