Open Poser.  Go to your Windows menu (I think). Find the Python Scripts".  Click "Utilities", and then "Uncompress files".  Browse to the folder you want to uncompress (doesn't have to be the runtime folder itself, it can be one of it's sub folders). Check the box next to "uncompress geometries" and click "run".

EDIT:  Cross posted.  But yeah, what Vince said.

"It is good to see ourselves as others see us. Try as we may, we are never
able to know ourselves fully as we are, especially the evil side of us.
This we can do only if we are not angry with our critics but will take in good
heart whatever they might have to say." - Ghandi