Publication of highly modified Micrograme FPS template

My case is that I highly modified and expanded Microgame FPS template by Unity Technologies and would like to publish it in Asset store with reffering to that I based it on Microgame FPS template. Is it allowed or it's still a violation of rules?

P.S. I am not sure if I should consider it as one of Standard Assets (with their own rules of redistribution) or not. That's another my question