Terrain Background Image

In the features a google maps screenshot or an aerial photograph is mentioned (to be used as a canvas background, I assume). I would like to use this feature, but I can't figure out, how to upload the background image or how the paste a screenshot.

Could anyone walk me through this process or give a hint where I might find this feature documented?

Thank you very much.

Thank you so much. That worked great!
Im using an Android Tablet. When entering a numeric value for the image scale slider, it seems there is no way to apply the numeric value. Enter-Key on the on-screen keyboard had no effect.
I managed to get the slider close to the desired value, so I'm not stuck at the moment. Am missing something?
Great software! Thanks!

First of all: Thanks for your quick support and for providing Track for free. This can't be appreciated enough. So thank you big time.

I will look into the feature requests soon. However I would like to check the functionality on a PC first. If this works on a PC that's perfect.

I only would like use the tablet for convenience. To check where I am when I'm commuting. If the base settings work fine on a PC, I'm totally content with Trax.

Cheers,
Mirco