Hi Neil,
assuming that your product has:
Program Name=MyCad
Product Name=My CAD
Visible Release=2024
Registry Release=4
Comany Name=My Company
then you must:
Delete the folder %APPDATA%\My Company\My CAD 2024
Delete the folder %LOCALAPPDATA%\My Company\My CAD 2024
Delete the reg key HKEY_CURRENT_USER\Software\My Company\My CAD\R4
Claudio