Silver Efex 3.0 has PS Smart filter bugs: can't open past images; leaves checkerboard artifacts

Working with variously sized images on a 16" MacBook Pro running Catalina 10.15.7 with PS 22.4.2. After upgrading to Silver Efex 3 I cannot reopen smart object photos (either PS or LR versions) previously edited with Silver Efex 2. I believe this is an issue with the latest version of Color Efex as well.

Also, Silver Efex 3 seemingly cannot process on top of other smart filters in PS. If I run Dfine 2 or Topaz DeNoise before running Silver Efex, the lighter portions of the resulting image are covered with a checkerboard-like set of artifacts that are apparently baked into the file (sample below showing the result of applying only the Full Dynamic Harsh preset).

Is this user error or are these bugs that will eventually be corrected? If the latter, are there any current work-arounds? If not, how do I downgrade to the previous version of NIK?

see Issues with Nik4 - #8 by Wolfgang (Windows)