When I purchased the PICK Ultimate from YURI it was zips inside a zip. If this was the case with you I assume you unzipped to a temp folder first.

Using Explorer you should see a Runtime folder inside Poser extra Stuff

Inside Runtime you should see Geometries, Libraries, Textures and probably Pick Manual

Inside Libraries you should have Props and Materials folders with a PICK folder in both

There will be more folders inside all of the above

Using POSER there will be a PICK folder in the Props and Materials sections only and folders inside these

Any problems then you can delete everything in the Extra Poser Stuff folder and extract again. Poser does a scan at start up for any changes to its runtimes.

By default Windows lets you use zip files as folders- the icon is the same until you install WinZip or 7Zip etc. Poser cannot read them

Poser 11 , 180Gb in 8 Runtimes, PaintShop Pro 9
Windows 7 64 bit, Avast AV, Comodo Firewall
Intel Q9550 Quad Core cpu,  16Gb RAM, 250Gb + 250Gb +160Gb HD, GeForce GTX 1060