This does not work anymore. I want when I select some files and click the button, the files get deleted and you get some zero sized files with the same names and extension .seen.
That command seems to work OK here in Opus 12, as long as it is set to MS-DOS Batch (since it uses the DOS "type" command).
You can create empty files without using external commands, however. This works when set to the normal mode, and will also work in more places (e.g. if UAC elevation is required to create the files):