The Ruby plugin you linked is for IntelliJ IDEA Ultimate only, it will not work with PhpStorm. See this answer for more details.
However, you can get basic syntax highlighting for Ruby files in PhpStorm using the TextMate bundles support plugin. It is already included in PhpStorm 6.0.1 and you do not need to install it, just make sure it is included in Settings | Plugins

For some reason, support for PhpStorm TextMate Bundles does not recognize *.rb files supported by this package. To fix this problem, open the file Ruby.tmbundle\Syntaxes\Ruby.plist in a text editor, find the <key>fileTypes</key> section, add the <string>rb</string> in the <array>
(the above should be fixed in the latest version of the Ruby package, so editing the package is no longer required, but if you add any other language pack, this is what you may need to configure)
Restart PhpStorm, make sure *.rb now properly bound:

Now you get Ruby syntax highlighting in PhpStorm:

If you need full support for both Ruby and PHP (plus much more) in the same IDE, consider using IntelliJ IDEA Ultimate .
CrazyCoder May 08 '13 at 23:16 2013-05-08 23:16
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