The Open action is not always what double-click will use. It has probably been overridden using the Open With dialog in Windows, which should make the open action irrelevant.
Is the issue only with what you see in the File Types dialog, or is Photoshop actually handling the files on double-click? Try using the Open With menu to change the default app if needed.
On the Actions tab, you would not want to use {f} in commands as that's an Opus code and nothing else will understand it. Those commands need to work in Explorer as well. Both Opus and Explorer understand "%1" so that is safe to use there.
Check the Events tab as well, in case you've overridden the double-click action within Opus. (The Events tab doesn't affect Explorer or anything but Opus.)