This is a boot disk - linux based:
http://home.eunet.no/~pnordahl/ntpasswd/

It will edit the registry. It is primarily used to reset administrative password. It also accesses the registry. Registry writes to NT form linux are hazardous if you are creating or expanding the file. If you tinker a file and write it back, it apparently does not cause difficulties. This utility has been around for 4-5 years that I am aware of and doesn't cause problems.

Read the website for conditions and uses. The editor is a little clunky as a registry editor, but it works. You can also copy the registry hives off to the floppy to better peruse or analyze them.

Dick