hi David Groh, its your server trying to disable this functionality.
on updating plugin, server need to download the file, extract, and activating it.
it will require quite long time to execute the code.
this function (set_time_limit) prevent server to stop the process until its finished.
we can provide you where to change, but the updating process may have issue because it will still need sometime to finish.
other solution as i write above, you can find the plugin into jnews (themes) folder > plugin. all plugin including with this themes is packed into this folder.