ewk

You grab the window template, delete the anything within the window frame, apply a black color to it with the opacity level of your choice (where 0 is fully transparent and 255 is fully solid, for a really tinted window I'd use 245) once you've applied that, you select the window sticker and just copy paste it over the black translucent window.
 
If you want the image to be translucent as well, you need to apply a fully black color with the opacity of 255 (so it's solid), then apply your image where you want it to be. You can make that image black and white with Paint.NET's built it tool if you want it, or you can do whatever you want with it. When you're done, select the whole black area with the image as well and with the trasparency tool change the opacity to 245 or whatever you want.

Just download Rage Native ui 1.8.2 😉