You need to put in a value for the collar length, auto does not work.
Are you saying you are getting your outer collar developed?
I've tested 23-24 - collar not Auto, and varying from 3-12 inches long.... no outer collars for DW.
If you're getting collars then it might not be a bug, rather a setting/checkbox causing the issue, but I am not familiar with any setting to toggle inner/outer collars.