Responsive HTML output file name?

Been searching for two days and cannot find an answer, but for Responsive HTML output from Framemaker, is there any way to customize the launch file from "index.html"?  We want to move to responsive help for all our apps, but as much as we always insisted they should launch from an "index.html" page, they all have a custom one.

Is there a setting I'm missing or anything in the files that also needs to be updated if you need a different launch name?

- V