Hi Hornwitser !
I really like the idea of offering a lot of flask designs for modders. I find them really high quality and simple to use so thank you.
As the title of the thread says, would it be possible in the future to have a larger range of colors ? Or perhaps some way to input RGB or hex colors in the code to choose a color ?

Adding new colours is a possibilty, but any new colours should be distinguishable from the existing set of colours otherwise you'll have identical looking flasks.

I tried to make the color variations using tinted overlays at first, but the results looked really bad and I couldn't figure out a way to make it pretty. I ended up rendering each bottle in each colour to work around this. For that reason it's very unlikely that there will be a way to input RGB values and get a colour (unless someone can find a way to make tinted layers look good, I couldn't.)