Comment 18 for bug 539324

Another workaround similar to Sebasitan's is to choose "Yes" when you get the error message to go back to the summary screen. Select the swap partition, hit Enter to modify it, choose "swap" as the type and hit Enter again. Then scroll down and select "Finish" to complete the installation. It seems to complete successfully after that without the necessity of manually setting up the swap partition after the first boot. The swap partition does appear in /etc/fstab.