I WAS successfully using this plugin without any issues with the following configuration:
AWS Linux
3.14.19-17.43.amzn1.x86_64
FFv25 & FFv31
Jenkins version 1.554.2 hosted on AWS Linux
Selenium Hub/Nodes on AWS Linux
Selenium Grid plugin version: 2.41
I upgraded Jenkins to latest in Feb 2015 (v1.598) and the plugin stopped working. Then i got the latest plugin (v2.44) , compiled it locally in Mac Pro and manually added the hpi file to the jenkins.

The setup (Grid/Node/Jenkins/Plugin) as such was working. But automations were failing because of the following reason:
The webpages that were opened in FF, the page source were encoded in weird characters especially the <, > and = signs of html.

Because we rely on these to access certain elements using regexp etc, majority of our automation started failing.

I downgraded the plugin to the previous version (v2.41) and all started working again.

Some changes between 2.41 and 2.44 introduced some kind of encoding when Webdriver instances is created or when Browsers are invoked.
This is blocking me from upgrading to the latest.