I've just switched from Reaper since I like cgminers API, and is much more configurable than Reaper. The problem is, every time I get an accepted share, it doesn't count properly, but yet increases in 512 each time. E.g "Accepted" A: 512, instead of "1". If I have 2 accepts, then it'll be 1024, etc. I cant really see how many shares it has accepted if this happens. This also goes for the rejects too.
cgminer now increments the Accepted count by "weighing" it with the share difficulty of the pool. It sounds like you are mining on a pool with share difficulty of 512. This means, in cgminer at least, it will display each accepted share as 512.
You can see the same in bfgminer (if you wish) by running it with the --weighed-stats argument.