Hi @cridum,
It appears that other users have experienced issues tied to this plugin. See here: https://forum.pkp.sfu.ca/search?q=Citation%20Style%20Language%20500
A few them appear to be tied to 3.1, but more so, this post in particular where a user encounters the issue seems to be related to the plugin not being installed from the plugin gallery, which seems to address the issue: [OJS 3] Upgrade plugin Citation Style Language make website unreachable - #12 by waluyo
For your other issue, can you please post this as a separate forum post (and please include your OJS version number, steps taken to address the issue, as well as any relevant error messages)? We prefer to limit forum threads to one issue, as this helps keep the forum organized, and assists users in identifying solutions to issues.
-Roger
PKP Team