Hello,
we finally managed to get everything sorted out (big thank you to John McIntosh!) and are making an updated version of the Mac OS X squeakland installer available: http://squeakland.org/installers/SqueaklandInstaller.dmg
We also added it to the download page, you may need to clear your cache or force reload to see the new link.
Please let us know if the new version fixes your problems.
Thanks
Michael