It's really not all that difficult, and from what I've read, it's nearly impossible to disable or brick the Roku DVP.
The instructions in the README are pretty good, and the installation of the channel on your Roku is really simplified with the installer that el.wubo has created. If you get stuck, there are several people who are using his custom channel that could help you out. Just post in the thread calicommando linked to above. If a user can't help you, el.wubo (the author of the channel) can. He is very responsive and helpful.
Just keep in mind your files will need to be in a Roku-friendly format, which is a bit of a hassle when it comes to movies since the Roku only supports certain formats. Transcoding videos takes time...a lot of time.