For those people who still have the problem, please make a clean uninstall (don't make any leftover files, folders and including registries) PlusSpec with Revo Uninstaller, clean again the registry with CCleaner. Restart your laptop/computer.
Here's the steps (careful and take it slowly):
1) Turn off your internet connection, close all opened application and disable you antivirus temporary.
2) Install PlusSpec as administrator... wait till it finish.
3) Make a "Temporary new folder" and extract rar file from the link above that @bong2x gave to us about fixed issue. There are some folders on this new folder, copy and paste each folder to:
A) App_SU2015 contains: Gem64 which found at App/Roaming/SU2015, Copy and paste 'em all.
B) SU2015 tools contains: (RubySTDLib, extension.rb; etc) which is found at Program file/SU2015/tool. Copy and paste 'em all.
C) SU_plugin contains rubysketch_plusspec found at the C:\Users\yourcomputername\AppData\Roaming\SketchUp \SketchUp 2015\SketchUp\Plugins. Copy and paste 'em all.
D) C Folder contains: Ruby folder. Copy and paste 'em all to drive C (or to your system drive).
4) Copy kg_plusspec.exe to C:\Users\XXXXX\AppData\Local\rubysketch\license .. Run as an administrator --> type your name (Your computer name, which can be found on "my computer" properties. kindly do not type your real name, fake name or even your girlfriend name or this medicine will not working), generate it and.. --> Voila, you're registered if "plusspec-prerelease.json" file there.
5) You almost there.. Throw away your "Temporary New Folder" that you've just made to recycle bin and remove it from your drive.
6) Activate your internet connection and enable your anti virus.
7) Open your SketchUp 2015 as an administrator and wait until PlusSpec plugin finish to load.
Hope it may works and useful for ya......... Sit back, design and enjoy
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