How can I add transparent png files?

In Photoshop you can’t see the shadow on black! But on blue!

In Facer the shadow is visible on black! How can I make it look like in Photoshop ?

Is the shadow with #000000 and some transparency or is it grey?

If you can attach the file, we can help you a little better. My guess is that your layer order is different in Facer editor or you are exporting without alpha channel. Can’t be certain unless I can see the watch. Also link your watch face as inspectable so we can take a peek how you are creating it.