And what is "a multi string variable" used as descriptive test for what to run. Generally, this will be a word or words describing the command to be executed.
Examples:
- MyCompanyInventoryProgram
- Runs Once a Day
- DoNotRemove
- Junk

Try this to test:
WRITEVALUE ("HKEY_CURRENT_USER\Software\Microsoft", "TestRegWrite", "Success", "REG_SZ")

If successful, you can find within the the key 'HKEY_CURRENT_USER\Software\Microsoft', in the right hand pane, a string value labeled 'TestRegWrite', and the data value within this will be 'Success'. This key selected for example as it must exist in your registry. As Radimus pointed out, the registry key "HKEY_CURRENT_USER\KiX32\one" likely does not exist, and can not be written to unless created in advance using ADDKEY.

Bill