I had a similar experience when installing V3.1 NL
Did a clean install with new db and after submitting the data in step 1 I got a WordPress header on the step 2 page and nothing else.
Via phpmyadmin I saw the tables were created and contained data, but I clould not access any page in the admin area.
After removing all tables from the db I tried agian (after a fresh ftp upload of all files) with the same results. This time I did a (F5)refresh after step2 wouldn't show any info. This gave me a "max memory error" (set for 32MB btw).
I removed all files and uploaded V3. The install went smooth and next I upgraded to V3.1
This did the job but I assume there should be easier ways to get v3.1 installed.
Later on I also noticed a max mem message when I used quick edit to disable comments for the about page when I saved the settings.
Hope this helps your investigation.