Paddy not working with symbols
Hi,

I'm opening again this issue because I've just downloaded Paddy plugin and it doesn't work for me with symbols.

It works perfectly with groups(screenshot attached). Spacing and Distribution works perfectly too. Just with symbols.

I've tried with the Sample File included [in this tutorial](https://www.youtube.com/watch?v=FvBQm5qHwdc) (thinking that I was doing something wrong with the options or something) and it doesn't work either.  

My sketch version is 51.3
![captura de pantalla 2018-09-20 a las 12 05 54](https://user-images.githubusercontent.com/43438640/45811817-6e9f0400-bcce-11e8-8f51-edd28d33c0f0.png)
