If you successfully managed an installation with debian-installer, please take time to provide us with a report. There is a template named install-report.template in the /root directory of a freshly installed system. Please fill it out and file it as a bug against the package installation-reports, as explained in Section 5.3.5, “Submitting Installation Reports”.
If you did not reach base-config or ran into other trouble, you probably found a bug in debian-installer. To improve the installer it is necessary that we know about them, so please take the time to report them. You can use an installation report to report problems; if the install completely fails, see Section 5.3.4, “Bug Reporter”.