There are some bugs with normal and whether draco supports lossless coding

Hi, I'm using Draco to compress an OBj file that contains texture coordinates and normals. I want a lossless result, so I'm going to set all qp's to 0. But when I decoded it, I found that all normals in the decoded OBj file were exactly the same. There must be something wrong with this.
By the way, I set cl to 10. Did that make a difference with cl 7(defalut)? And whether it only affects attributes compression or connectivity compression as well.
Thanks!