>Do prices rise when consumers have more money to spend? Is consumer inflation tied to employment rates? Does inflation slow when poverty grows?

Pretty much, but that's not a flaw of UBI, that's how the economy works and if the amount of UBI is picked carefully by skilled economists it would be very easy to achieve the desired amount of inflation. Everyone is somehow scared of inflation because we have been in deflation or at least near zero inflation for at least a decade.