Looks as though kickseed (0.48) has not been updated to reflect the recent changes to grub-installer (https://cia.vc/stats/project/grub-installer, 00:54 on Apr 15).
The installer fails with "grub-installer: error: Preseeding of encrypted passwords changed! Check installation guide." It appears to me that kickseed's bootloader.sh handler is passing a boolean to 'grub-installer/password-crypted' rather than an MD5 checksum and is not setting 'grub-installer/password-again'.
TEST CASE:
1) Create a file on an HTTP server containing just the line 'bootloader --md5pass $1$eURfjafX$MhF/cvWmFQWYXkCHpt1tM1' (that's an MD5-crypted version of 'foo').
2) Boot from the alternate or server install CD; press F6 at the boot menu and add 'ks=URL' to the boot menu, where 'URL' is the URL to the file you created in step 1.
3) Install as normal. On failure, the error described in the bug will occur (displayed in the syslog or on Alt-F4); on success, the installation will proceed normally. When the GRUB menu is displayed after the first reboot (you may have to press Escape to get it to be displayed), trying to edit a menu entry by pressing 'e' should require the password 'foo'.
Thanks! I've committed a fix upstream and will backport this for 8.04.1.