this morning I woke up and I found out that rejected shares are now around 4-5%.
(...) Is there something going wrong?
I am also seeing a higher reject rate at the moment:
We're experiencing some growing pains. We will focus on minimizing stale and invalid shares in the coming days. Until levels are back to normal we have closed registration.
what does unknown work mean, never seen that before
The unknown-work error code means that the work you are submitting has either never been handed out to that specific worker, or that the work was expired because it is older than 120 seconds. This error should only occur for workers below 100Mh/s, and when we restart our backends for updates (ca. two times daily).
(...) if I do an instant cash out it does not subtract the donation that is set inside My Account->Account Details.
Is this by design or am I wrong?
This is by design. Your donation is already being subtracted from the PPS amount each time we process incoming shares. Since last week we've been keeping track of those donations, and we plan on displaying them in your stats.
Oh, and have we thanked you yet for your donations? Thanks!