Yes, I have the Milky Way Goat Milk Guest Soap tray mold and have used it for Goat Milk soap. I started using SL at some point after I got tired of always rubbing the lanolin into molds and not always getting as fine a film on them as desired. Good for my hands, as I love lanolin on my skin, but very time consuming, too. So I ordered some SL and started using that. Now I'm liking vinegar in soaps and might one day give it a try and see if it helps with releasing soaps from the Milky Ways molds faster. I'd just have to do the calculations and so on, which is also a bit time consumptive. But it does harden up the soaps faster.
Oh, to answer your question about how long I kept the GM soap in the mold, I've only done this once and looking back on my notes did not write down how long I left it in the mold. I see I used salt as well as SL, so maybe a bit of overkill, but I know the detail remained on the soaps and they look nice. My SIL wanted some guest size soaps, so I thought making them as GM with that mold would be a nice touch. I do know this one never went into my freezer because there's usually not enough room for a tray mold in mine.