I have also tried to install the DMS module into my companies website for some basic document management and I have the same problem,
I have copied the folder into the home directory, renamed it to "dms", emptied the cache and rebuilt the database but I can't access the backed, I too get the same problem "internal server error", is there something that I am missing?
Please read the FAQ before posting. A 500 internal server error is a generic error, check your error logs for the actual error message or turn on dev mode. One thing I would check from experience is make sure the dms-assets folder (where DMS assets are stored) is writable by the web server.
This news is unfortunately very difficult to find as it makes no mention of this in the readme file, or anywhere on Github from what I can see. It only mentions: "PHP 5.3 with the "fileinfo" module (or alternatively the "whereis" and "file" Unix commands)"