Hi andfly !
I found out your magic trick for the digital displays ! 
Its what I was suspecting ...not sure if I can reveal it. Normally magician don't reveal their tricks 
There is no secret to keep!
Numeric displays are actually a series of cylindrical rollers with a texture made of simple digits from 0 to 9.
Obviously you can also put the signs "+" and "-" in the leftmost roller or characters or writings ...
The number to be displayed is converted into a string and the characters are extracted one at a time.
The numeric value of each character is used to determine the appropriate cylinder rotation for that digit.
It is not a new idea ... before the mass electronics was widespread it was a system widely used for all apparatuses that had to display numbers mechanically, using extremely ingenious and complicated gear systems.
Making a transparent screen is also very simple.
You can use a 2D mesh but I prefer 3D (very thin) because, in this way, it is also seen from behind.
If you use 2D mesh the screen can only be seen from one side, on the other it will be completely invisible (it could be useful in particular cases).
The play of transparency is given by a suitable opacity texture.
The main texture of the screen is created (better if simple, even better if of uniform color and, in any case, with clean lines without gradients).
You save it (in dds) as DXT1 and use it as tex.albedo.
Then the colors are inverted (if monochromatic it is convenient to transform it into black and white and make the negative)
Save the negative as BC4 / ATI1 and use it as tex.opacity.
In Outerra only the "albedo" part will be visible and the rest will be transparent.
I also made non-monochrome screens ... sometimes the result satisfied me other times it was a mess ... you have to try.
Even the mobile indexes are small 3D objects with very low thickness.
At the beginning I had made them semi-transparent and positioned behind the screen then I preferred to put them in front of the screen to take advantage of the possibility of emissive textures, which can also be seen in the dark without needing to be illuminated.
How to avoid the shadow ? Simple, the indexes should be positioned very close to the screen almost touching it.
Unfortunately, a screen built in this way should be illuminated.
You cannot use emissive textures to not lose the transparency effect given by the opacity texture.
Good job
