Thank you for your reply. Just found the comments in the assembly manual...seems to be a common problem. I am going to remove the zip tie entirely: the temp sensor seems pretty secure without the zip tie.

Posted by: @carl-2

I am now assembling the Core One and about half way through. One thing i have noticed is that the top belt teeth are in contact with a zip tie on the plate for the two fans. Even when i put the belt under tension it is still in contact. Is this normal?

No it's not normal. The Core One Assembly Manual has a specific instructions to ensure the zip tie is pushed down enough that it doesn't interfere with the belt. I would remove the fan cover, cut off the zip tie and replace it but ensure it's flatter. You could even remove it entirely.