Profile: milspec-direct

I'm having trouble installing the plugin. I've copied and pasted the plugin into my plugin folder, and I already have the SevenSpikes.Core folder existing in my plugin directory previously, so I don't want to overwrite any of my files.

So, I only took the plugin files and not the core files and put it into my plugin directory. It resulted in my site crashing, so I had to remove the new plugin files to bring my site back up.

Must I overwrite my core files with the ones that are provided to me when downloading the sale of the day plugin?