SPEC EXPORT PLUGIN how to install this.
This plugin (https://github.com/utom/sketch-measure) contains not supported code. It has an Objective-C part. So, this plugin needs to be modified before using in Lunacy.
Lunacy could run JS plugins only. The plugin should not contain any Objective-C or Cocao script parts, and no special Mac OS calls too.
You could ask the developer to adapt this plugin for Lunacy.
It'll be very nice if the developer will find it possible to modify it in view of the coming Mac OS and Linux versions of Lunacy.
We'll add it to the list of tested plugins in the Plugins tab of Lunacy if the developer will adapt it.