** Constants
#DEFINE HKEY_LOCAL_MACHINE -2147483646
#DEFINE REG_TEST_KEY "Software\RegTest\Test1\Test2"

** Register the function
DECLARE INTEGER RegDeleteKey IN Win32API; 
  INTEGER iBaseKey,;
  STRING sSubKey

** Call the function
=RegDeleteKey(HKEY_LOCAL_MACHINE, REG_TEST_KEY)