in the FAQ there's explained how to remove Windows items from context menus ([url]Crash, exit or high CPU when right-clicking certain files]) and to add them if they they are hidden by default ([url]Tip: Organise and Speed-Up Context Menus]) respectively.
This works for all items in the file context menu (well, at least it seems so), but not all items in the folder context menu. There are some entries in HKEY_CLASSES_ROOT\Drive\shell that do not have a CLSID. Is there a way to remove (or add) them separately? I couldn't find out how to do it...
Those ones probably just run commands so you can create Opus context menu items which run the same commands.
Set the function type to the one that says it's for Opus only, rather than Opus and Explorer, to ensure it doesn't get hidden.
It was even easier than that - there were already entries in the context menu tabs of some file types; they just had been deactivated when I chose "Hide Windows items on file context menus" because they were of the type "Run an application". I would have thought that those items should still be visible since there were entries for them in the file type definitions...
Well, I created new entries of the type "Run an Opus function", and now it works. It's a little bit lavish to modify all the entries of the system file types ("Edit with..." etc.), but it works. I just wonder why the function type of existing entries can't be changed from "Standard Function (Opus or external)" or "MS-DOS Batch Function" to "Run an application" or "DDE command" once an entry exists - the corresponding options are missing in the dropdown list. Because of this I always have to create new entries and to delete the old ones instead of just modifying them.
The "Hide Windows items on file context menus" is badly named. What it really means is "Hide non-Opus items on file context menus."
The way you can't always change the type of existing context menu items is also a little annoying, I agree. I think it's because the different types are saved in different places but Opus could be clever and move commands when their types are changed.