Theme Editor Missing, All Css Gone After Cache Cleared

I installed a currency addon yesterday and cleared my sites cache. Im not sure what happened after that but I was unable to open up my site at all. Yet I could access the backend admin. The error was looking for in the common folder. I created the file and the site came back up. The problem now is that the on site theme editor is just blank with no way of moving or closing it. Non of my moving parts on the site are working (ie. Sliders, CSS etc).

Any help would be greatly appreciated.