After my fork also touched my red frame and the headset couldn't be adjusted properly, I also got the spacer.  But it really doesn't work... so it was dismantled again.  then completely sanded the frame on the lower headset bearing until the paint was gone.  Since I had already driven a few kilometers before, I could clearly see drag marks.  After grinding there was finally no more grinding between frame and fork and the headset bearing could be adjusted.  Despite the small improvements, a great frame!