Welcome back.
Question 1: Is the stack above supported for the CDCE?
Although we no longer support 32-bit OSs. We provide 32-bit shared objects to provide backwards compatibility.
Question 2: Any ideas, tips, troubleshooting to-do's?
Hard to help you here given all the changes that you've made. The easiest time to fix the problem was just after the reboot.
I would re-read the Samba Integration document and look around in the community, there are many articles related to resolutions to these types of issues.
Resources:
docs: https://docs.centrify.com/en/css/suite2017.1/centrify-adbindproxy-guide.pdf
R.P