Continue button after error during install

This issue was noticed during an attempt to install drupal 6.x-dev from the development snapshot tarball.

If you don't provide access to the ./sites/default folder, you get the following error message before the 'setup database' step:

Drupal database setup
The following error must be resolved before you can continue the installation process:
The Drupal installer requires write permissions to ./sites/default during the installation process.

A screenshot of the page is attached.

You are not presented with any information regarding what to do once the error has been resolved. I pressed my browsers back button and then repeated the previous step, but that did not feel right as I had no idea what behind the scenes changes had taken place between steps.

A 'Continue' button along with the following message would be very helpful:

Please resolve the error and then click on the continue button.

This is just a usability issue, but this could well be the very first error that a new user encounters. To make the best possible impression on that new user, we need to make things as simple as possible.