Just installed dapper alternate and got a warning at the installation of the third line of the second step: 

"apt-get build-dep linux-image-$(uname -r) ubiquity update-manager ubuntu-artwork base-files ubuntu-meta "
"attention - chosing libdebian-installer4-dev instead of libdebian-installer-dev"

I chose "yes, thats ok" - but just in case you are not aware of this behavior.

Afterwards, the apt-get broke with the message:
"was not able to get "http://at.archive.ubuntu.com/ubuntu/pool/main/t/t1lib/libt1-5_5.1.0-2_i386.deb - md5sum not correct"

after i retried to "apt-get build-dep" it, i just got that message:
"build-dependency fpr ubiquity is not possible."

so i removed ubiquity from the line and tried again, now i got the same error with ubuntu-artwork. I removed that too.

Now it wored. Installations started.


looked at ubiquitys dependaces: installed hfsutils, libdebconfclient0, localechooser-data, os-prober, python-apt ubiquity-ubuntu-artwork, ubiquity-caspar,  and stoped at ubiquity-frontend, cause it wanted to install a full X

so i looked at the build-dependecie s in the dsc-file

i installed bison, flex, grep-dctrl, libart-2.0-dev,  libdebconfclient0-dev, libdebian-installer4-dev, libglib2.0-dev, libgtk2.0-dev ... the last one threw another error: "libgetk2.0-dev depends on libbpango1.0-dev - but shall not be installed and libcairo2-dev - but shall not be  installed - broken packages"