Add capability of setting thumbnails + "autosave" of sorts...?

[jPress05]

Firstly, forgive me if this is not how I should create a feature request, I have never done this before, but I Love the app so far, it's super intuitive, and having made the switch from Dynaper I can safely say I prefer it. However, what both apps appeared to lack was the ability to set a thumbnail for the image. I know that the thumbnails are stored in a generic location:
/System/Library/Desktop\ Pictures/.thumbnails
which I am assuming (like setting custom dynamic papers...) can be worked around by creating a directory at
/Library/Desktop\ Pictures/.thumbnails
My point being, the stock wallpapers, such as the light to dark ones, or the dynamic ones all have an overlay over the top to show the light and dark version of a paper, or (for the dynamics) the different frames of the image file. would it be possible for the app to auto generate a thumbnail like this for the user to move to their desired location? Or better still could the app gain the capability to do this on its own. i.e. the user is prompted and given the option to place the new dynamics into a
/Library/Desktop\ Pictures
folder etc along with the relevant thumbnail being placed in its suitable location...?

Once again, I love the app, and I will continue to use it regardless. Would definitely love to see this feature one day though :)