The new mouse is not even on a flat surface and unsteady when clicking.

Please inspect the mousefeet. If there are irregularities, use the spare set to replace the current one. If that does not prove successful, then it is abnormal, please contact us (ZOWIE website/Support/Contact/RMA) for further assistance.

How to change mousefeet?

https://www.facebook.com/watch/?v=10154189865108963