I took a fresh computer and loaded a fresh CMO with the official release (presumably v1.04.114749 though I didn't record this data) and the normal depth slide for wire-guided torpedoes was present.
I then opted for the Steam beta (1276.1) and it disappeared. I also have a second computer that I updated to 1277.1 where it's also missing (and where I first noticed the slide's absence).
I'd post a savegame, but it appears to be with any scenario/save (I used three: Pacific CSG-21 and Pacific Fury as tests but also my own quick scenario with just a ship & my Virginia II sub); and hope the sceenshot will be more useful.
Harder to make those sneak attacks without the slide!
Thank you!