Welcome to the forum!
All the INX and PY files need to be directly in that folder, and not inside another folder. There are a really lot of files, compared to most extensions - looks like approx 175 files.
Uumm.... Check to see if any other extensions are working. An easy one to test with is Extensions menu > Render > Gear. Just click Apply for whatever values are in there by default, and look to see whether a gear was drawn on the canvas.
If anything goes wrong, I would probably wonder whether you have Inkscape installed properly. Do you remember whether you unchecked Python during installation? For extensions to work, Inkscape needs Python. Although this is just a guess, and getting a little too far ahead, for the moment.
Let us know if any of that info helps.
