Hi, are you sure 100% sure you are seeing error :708? Can you screenshot the error?
I’m guessing what you are actually seeing is error :42, which is unrelated to the main topic of this thread. (it was a problem with v1.3 that was fixed in 1.3.1)
You need to upgrade to v1.3.1 or later.
V1.3.1 link for mac: http://natephotographic.com/wp-content/downloads/MAC-NEGATIVE-LAB-v1.3.1.zip
When you upgrade you need to follow the steps here:
In your case, it looks like you have a custom path setup for your plugin (/Volumes/Tiano Extra Space/MAC-NEGATIVE-LAB-v1.3.0/source/NegativeLabPro.lrplugin).
You should remove this in the Plugin Manager, by hitting the “remove” button.
Then create a fresh installation following the instructions in the guide: