build 2019.33840
The scale Z parameter on the geo sop instance tab seems to work incorrectly. It always scales the X-axis, please check.
It is working fine in my tests, are you sure you assigned the channel to the correct scale parameter on the Geo COMP. Please upload example files when you can so we can reproduce issues, attached is my working file.
SZinstance.1.toe (4.0 KB)