This is what worked for me. Hopefully it’ll help someone else.
Uninstall the 64 bit version of Ruby 2 (apparently, there are lot of libraries that haven’t been tested against 64 bit Ruby on Windows and it can lead to errors)
Download the latest 32 bit Ruby 2 version from here and install
Download the 32 bit version of the DevKit from the same link as above and follow these instructions to have it enhance your previously installed Ruby version
Download the 32 bit MySQL C connector (archive version) from here and unzip it to C:/mysql
Open...