We provide ZwFixIt tool for removing the residual data after uninstallation. However, we do not provide this tool since 2019SP1, because we combine this tool in the installer. After install, you can copy this exe file out, and uninstall, then run this command to clear the data.
You need to use the corresponding application to clear ZWCAD data. Use the one in 2019 to clear 2019, and 2020 for 2020.
You can find 2019 and 2020 tool in attachement, modify the file name, or you need to run the right command by file name