[Plugin: Shopp Default Breadcrumb Extender] impossible to use

Hi,

I am sorry the text is too confusing for you. Happy it made laugh though.
Working with WordPress you will run in to the phrase template file sooner or later coz that is actually the fundament of the whole system. But I remember being overwhelmed by it all in the beginning too.

Are you actually using the Shopp ecommerce plugin?
If not, this plugin will be of no use to you.
If you are, there is some good documentation on the Shopp website on how to install your Shopp template files.

The files that make up the Shopp plugin will tell WordPress how to display everything in your shop but you will most likely want to change that. You don’t want your shop to look like every other default Shopp shop. However it is not a good idea to change plugin files, as these changes get lost when you upgrade the plugin to a newer version.

Now there is where the template files come in. By setting up these Shopp template files you create your own copy of them. These will be preserved when you upgrade Shopp to a newer version.

In general, template files are added to your WordPress /themes/name-of-the-theme-you-use folder.

If you want to make the most of WordPress or/and Shopp, you will have to familiarize yourself with the system. Lucky for you there is tons of information on every aspect of it available on the internet. Your search-engine is your biggest friend in finding solutions.