Sorry, I can't help everybody... imposible
- If you want to know if your miner is working properly (and finding valids "nonce" for generate a block) , read this trick and try it (posted days ago)
Where we should see for results? Wallet log? because in miner log it does nothing unusual.
UPDATE: tried -t 20 instead of -t 10 and the results is many "found valid nonce", so it is working. Thanks! But the thing adaseb says is not that it is "not working", but that it's working about 3 times less effective than it should. Maybe something with internal cyclesize for multiple GPUs or something?..
And please, could you elaborate on this:
Hey everybody. Noticed something strange: often on new blocks they come with timestamps AHEAD of my wallet (and my wallet is perfectly synced with ntp, double checked), so my wallet says "Current block age: -30 seconds" or even "-50 seconds", or "-10 seconds" - you get it

negative values of TENS of seconds. Why is that? Is that only my problem?
https://www.screencast.com/t/rPEjrvGtbI thought that could be the problem with mining: if your computer is perfectly synced with time servers and finds a block, and simultaneously someone's computer is "ahead of time" and finds a block too - its HIS block included into network due to higher timestamp?.. How this network checks its current time and synchronizing? I think something is broken here, because it is very-very strange to have network-accepted blocks with timestamps ahead of world time servers by tens of seconds.