@Adriano Faria - I purchased this yesterday as I just upgraded my forum to 4.4.3 from 3.4.9 and we had an old version of this addon and my users really liked it.
After enabling the addon though, I noticed my board was much more sluggish, whereas it has been quite speedy since upgrading to 4.4.3.
This morning I awoke to CPU alerts (I am on a VPS), site up/down notices, etc. and could barely get into the ACP to disable your addon.
I should mention that it is the only addon installed besides "Who Was Online" addon found here:
Once I did disable your addon though, my board is back to normal, and is running fine.
I did see via Chrome's Console that there were a lot of timeouts, etc. when the addon was enabled.
What are my options at this point? I really like the addon, but if it's not an issue that can be resolved, I would appreciate you considering a refund.
Thanks for your efforts and let me know (either here or via PM) what can be done.