Hi Stephanie,
I was looking for a way to create an image slider in a custom module as well and the solution with Flickity was the first thing that actually worked for me - thanks! 
BUT - oddly enough the first image slider generated on my page doesn’t seem to work, although the ones following that one are fine. Any ideas what might be causing this?
http://gramm-medical-6269990.hs-sites.com/de/actiomedic/pflaster
Thank you so much in advance!
Sonja