https://docs.wallpaperengine.io

This will be the result of this guide: http://gtm.steamproxy.vip/sharedfiles/filedetails/?id=900945540

Open the editor by clicking this button in the main window:


Create a new 2D scene wallpaper:


Enter a title and choose the resolution of the image you want to animate:


Click OK.

Drag and drop the image ( http://publicdomainarchive.com/public-domain-images-blue-water-fall-nature-green-moss/ ) into the center view:


Select the image on the left, use the gizmos at the top to move or scale the image. If you entered the resolution in the beginning, the image should be centered already.



You can also adjust the optimal wallpaper resolution again in edit -> project settings if you need to.

Make sure the image is selected, then click Add Effect on the right:



Choose Water Ripple and apply it.


The effect will be auto selected for edit. You can also click on the image and then double click the effect to edit it. Click on Mask - Paint to begin drawing an opacity mask.


The paint brush tools are visible now. Change the value to 0 and click Clear, this will reset the entire mask to 0.


Now change the value to 255 and start drawing on the image. Draw the portions where you want the water to be animated by the ripple effect, in this case, just the water fall. Click OK to save the mask!


Adjust the remaining settings to tweak the effect, here are mine:

Click on 'renderable' at the top on the right to return to the image. Or click the image on the left.

Go to Add Effect again and choose Water Flow.



Edit the new Water Flow and click Flow map - Paint:



Start drawing on the water pond. Move the cursor in the direction you want the water to flow in. Click OK to save the mask!



If you drew over a portion you don't want to be animated, change the value to 0 and draw over it. This will make the image static again where you draw. Make sure to play with the opacity and hardness settings to draw smooth or with hard boundaries.

Adjust the remaining settings as you see fit. Here are mine:

Optionally you can add presets or foliage. Click on Add to add them:



I added light shafts and the fern model. You can also easily create your own ferns, just drag and drop them into the editor and add the Foliage Sway effect. Tweak their properties a bit to make them look more natural, otherwise their animations will be perfectly in sync.

Now all that's left is publishing the wallpaper to Steam Workshop. Click on Steam -> Prepare for publishing.



Choose a matching scheme color for the wallpaper and take a preview snapshot. Now the wallpaper can be published and shared with others, just click the publish button.