The spacers are totally fine, it rubs because there is not enough stack when you compress the headset. You just need to use some shims to add some height to whole stack. I have zero rub on my Time ADHX45 with provided 52mm bearing cover and related spacers, just had to use stock Deda compression ring to have enough height for the headset cover. You will have even less issues on your Btwin since it uses smaller bearing and you can use even round spacers and original bearing top cap.