See the first patch listed at http://pkp.sfu.ca/bugzilla/show_bug.cgi?id=8473
to correct the template typo resulting in the "|escape}".
I don't have specific experience with EndNote, so I can't comment on why content is being treated as a book; I wonder if that's the reason the year is being entered into the series title. If you're able to inspect the EndNote export and compare to another EndNote import that's successfully identified as a journal, please post the details here.
The DOI information is currently not provided to several citation formats, including EndNote; it's filed as a feature request at http://pkp.sfu.ca/bugzilla/show_bug.cgi?id=8415
Public Knowledge Project Team