I'm sorry, but I've been unable to extract the coder_v.4.zip without errors:

wget http://storage.googleapis.com/coder-images/coder_v0.4.zip
unzip -a coder_v0.4.zip
[snip]
inflating: coder_v0.4/raspi.img [binary]
error: invalid compressed data to inflate
[snip]

7zip also complains about the raspi.img portion, when extracting.

Is this an error I can safely ignore?

Thanks!