Can I suggest you put "total=0.5/0.0001" instead of "total=0.5". If you put a / and then a number, that changes the smallest amount that goes to any miner. If you don't, it defaults to 0.1, and anyone whose share would be less gets nothing.
When you're sending such small amounts, only the top few miners in the pool will get anything if you leave the cutoff at the default of 0.1. (And one lucky other miner will get all the other guys' bitcent fractions in a lump sum, at random, like a lottery).
Check the output of the wget command on its own to see the difference it makes...