Is it possible to change the section text for free downloads? I'm trying to distribute a freeware and premium version of a utility program.

It must be possible, because some games have free downloads with extra files only available if you pay at least a certain amount. If nobody else replies, try contacting Support.

An easy way to do that is to:

Set your price for the premium version and upload it.

Then upload your freeware version and tick the box: this is a demo and can be downloaded for free.