How to put faces on the watch

Look at this :

How do you convert a watchface zip file into an archive with the "watch" extension? When I open the watchface zips I just see a bunch of files. Nothing with the *.watch extension. Do you just change the zip extension to watch? Where are these watchface files that already have the "watch" extension? I keep searching, but can't figure this out.

I have Watchmaker Pro. Is there a way to do this in that app?

My domino 368 smartwatch with february '17 version of firmware has a limit of 20 !? watch faces
In x3+ i have over 400 wf
Is it normal? (The first question!!!)