Just activate it and the currency seems in the list.
The BGN is also in the list of currencies at the very bottom and you can select it..
I've installed the plugin but the prices remain in.
The plugin adds Bulgarian lev application to WooCommerce.
However you have to choose this application from WooCommerce settings yourself and to position correctly the currency symbol. лв....
You missed to set the location of the symbol didn't you.
Open WooCommerce Settings and go to Catalog tab.
There is Pricing Options stretchs and from Currency Position select the need one.
Browse the code recheck out SVN repository or subscribe to the development log RSS....
BGN Added to the list of currencies......
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