Am I doing something wrong?
no,
It is result of a set of winbuilder bugs.
Following guide and as you are already aware,
Plugin you download is at
AppsGS\Network\Remote Connect\UltraVNC
and if you download, it is now v24
you should already see "No Password" option.
If it does not show "v24" but "v23",
it is result of one of winbuilder bug of winbuilder bugs,
workaround is
click edit button on (over green small play button)
AppGS\Network\Remote Connect\UltraVNC
plugin
than click "source" button at top
you will see
[Main]
....
Version=024
and when you click red X button to go back to builder interface,
AppGS\Network\Remote Connect\UltraVNC
will show v24

winbuilder is very bugfull, and includes lots of bug workarounds even on plugin code level,
still things we develop and distribute on projects here works as intended.

