I figured this out, the page kept stopping and wouldn't let me go on. I thought it had to do with the mod_rewrite warning, but it needed the admin password. It might help to flag those fields as required if they aren't filled in.
We've moved the forum!
Please use forum.silverstripe.org for any new questions
(announcement).
The forum archive will stick around, but will be read only.
You can also use our Slack channel
or StackOverflow to ask for help.
Check out our community overview for more options to contribute.
This is one change that will appear in SS 2.4. You have to fill out the admin username/email and password or installation won't proceed, and an error is given at the top of the installer.