Any way to recreate my Gallery effect in Squarespace 7.1?

I'm getting ready to upgrade my website to Squarespace 7.1, but I'm worried I may not be able to use the same transition effect on my home page at www.HMS-inc.net.  Right now, I use a gallery at the top of the page with each image fading to the next.  Each image has the same layout, so it looks like a few parts of the image change at a time.  (If you don't see the transition, then please wait a few seconds for the page to finish loading.

When I made a copy of my website to test Squarespace 7.1, I couldn't determine how to make that same effect.  Does anyone know how I can get that sort of effect in Squarespace 7.1?  I'd rather not have my team together to agree on a home page.  Thank you!