I got to thinking about this, and Just for giggles - and to make sure all things were as equal as possible - I just installed the last version (origin.0.4) on a test site, then let WordPress do the automatic update to version 0.5, and what do you know... I did indeed duplicate your errors.
The following themes are installed but incomplete. Themes must have a stylesheet and a template.
Origin Template is missing.
After a visual inspection of the 0.5 download, there appears to be no index.php (style sheet looks okay) in the origin.0.5 package. I'm looking at it right now. I have no explanation as to why the install of 0.5 I did yesterday worked just fine.
 and I just downloaded it again, and now there is SEVERAL more files, including the index.php ????? I have two directories on my desktop, of the same theme 0.5, downloaded only minutes apart from each other, and there is indeed dramatic differences in the number of files in the archives. Now we have a mystery. :-)
[re-edit] - additional info (if relevant at this point) downloaded to WIN 7 using FF, WordPress test install is running on CentOS 6.3