AI image generator

Hi Community!

I've been trying to generate flat UI design images and icons using Articulate's AI generator in SL360, but some details of my prompts are simply ignored. We're using vector graphics (exported as PNGs) in our courses with transparent/no background, and I'd like to do the same in SL, however, I couldn't figure out a way to generate images with no/transparent background. It simply doesn't care if I add this part to the prompt or the style description. 

Any tips or tricks regarding this issue?

Thanks, 

Attila