Fisrtly, try and post code correctly in the forum, see:
- [How to] Post correctly formatted and colorized code on the forum? - Developers - SketchUp Community
Yes, I myself do not use it as the rules are often subjective most especially with regard to Ruby core code styling. Its rules file can be tweaked (in yml files) to remove some of the more “nitty” subjective rules.
Normally you run this in a standalone Ruby instance matching what SketchUp runs under (currently Ruby 3.3.2) but I suppose if Ruby 3.x changes are causing issues, then try installing Ruby 2.7.7 and run it under that.
There are quite a few open issues in this gem:
Scanning these quickly, I would suggest ensuring that your code files are encoded as UTF-8 without bit order mark.
I myself always use the magic comment as the 1st line of every code file:
# encoding: UTF-8
… even though (supposedly) after Ruby 2.0 the default script encoding is “UTF-8”
For more information see the introduction explained in the Ruby Script Encoding.
* Note that this paragraph has been removed from Ruby 3.x documentation.
Another possible problem can occur if the wrong properties are chosen when zipping up the RBZ archive. Generally, the built-in Windows context menu “Send to compressed folder” creates good zip files that are accepted by the EW and installable by the SketchUp Extension Manager.