Transferring GitLab to another server - need help

We have GitLab 5.1.0 be39106 installed on FreeBSD 8.1-RELEASE # 0, and I need to transfer it to the Debian virtual machine.

I created a backup:

cd /home/git/gitlab/
bundle exec rake gitlab:backup:create RAILS_ENV=production

The result is a tar file of about 2 GB.

Next, I tried to find the Gitlab package version 5.1 for Debian, but the earliest that I could find is gitlab_6.8.1-omnibus.4-1_amd64.deb at https://about.gitlab.com/downloads/archives/.
Installed it in Debian 7, but when I tried to restore backup I received the expected message:

GitLab version mismatch: Your current GitLab version (6.9.2) differs from the GitLab version in the backup!
Please switch to the following version and try again: version: be39106af73cc89098c290574da2be1488e76a7e
Hint: git checkout vbe39106af73cc89098c290574da2be1488e76a7e

Then I tried to install GitLab 5.1 from the sources: https://gitlab.com/gitlab-org/gitlab-ci/blob/5-1-stable/doc/install/installation.md

It seems that everything has been established, except Runners (the link does not work), and even the site opens.
However, I can not log in with a username / password:

root
5iveL!fe

And password “password” also does not work.

Tell me, please, how would I install this GitLab on the virtual machine, so that the backup of our old gitlab would sway in it?

Hello,
try this:
user: root
password: password