Created attachment 675207 [details]
Installation log (if more file are needed, please tell me)

I tried (several times) to install the Tumbleweed 20160430 DVD image on a
Thinkpad W520 (which up to this point contained an openSUSE 13.2 x86-64
installation) from USB drive.

It stops at the system analysis stage with the call to an undefined method
`reject!' for nil:NilClass at bootloader/stage1.rb:97 in `custom_devices' (for
details see attached logs). Trying to skip over this error (and some
subsequent) results in the system being formatted without the installation of
any packages.

I checked the installation image from inside the installation process and it is
fine.