The PayWithPoints scheme requires multiples of 2000 points.
You're allowed to pay 1000 points for the first 20E however.
Has anyone tried to book say a 90E room and book the first 20E online with 1000 points and the next 80E with 4000 points at checkout? Seems like it would work and be a good way to tighten the loop to make any multiple of 20E usable with points.