Hi, tdi2001 and, as stardepp said, welcome!
First off, thanks for your kind comments and I'm glad you like this skin. I actually did the light version first as it was what I was after, then felt I should provide a dark version as well.
The stop button can be actioned as stardepp stated and as you can see from the picture posted, Ctrl+S can also invoke an immediate stop. However, a not so well publicised way of getting a stop button displayed also exists:
When a track is playing (with your cursor anwhere over the main player), press and hold the SHIFT key on your keyboard. The PAUSE button will change to display a STOP button which can then be clicked. It won't work , however, if you have album art displayed in the main player which I haven't worked out if that is a bug or a design feature.
It took me some time to realise this when I first started and I now make sure that I include an appropriately designed stop button with each skin e.g. highlighted in the skin's theme.
Hope this helps.