Looks to me like TGuyus does not understand what you do, when you said:

Quote - mine are setup as Runtime and whatever category it is, then underneath that folder is the real folder called runtime and everything that follows according to Poser logic. 

RESPONSE:  I originally read it as similar to my situation unless they are saying that their Poser 6 program and runtime are on the external drive.  All of my separate runtimes are on an external drive, but Poser7 is on my main system drive (C).

Since Poser 7 SR3, the ability to have a runtime NOT called runtime was dropped.

RESPONSE:  I didn't know you could ever change the name from runtime to something else.

You can have a parent folder for it, named how you like, but it must CONTAIN a folder called Runtime. This is not a new behavior of Poser 8, but of Poser 7.

RESPONSE:  All of my external runtimes (see image) reside on their own external drive called Runtimes.  Underneath that they are laid out specifically as shown in the image.

The rule is, you need a wrapper folder and it can be called anything you like. In that must be a folder called Runtime. The name of the wrapper will be shown in the GUI. This is Poser 7 SR3 and Poser 8 and Poser Pro behavior.

Your runtimes will work fine, because you have them structured correctly.

RESPONSE:  I hope so.  I spent several years reorganizing them and I'm stlil not completely satisfied.  That's why the category thing in P8 sounds intriguing.  I always wanted to create a list of what props/items I have and where they're located.  I'm always hunting for things and usually not finding them especially when props are included with clothing items and in a different runtime.

Poser 2, 3, 4, 5, 6, 7, 8, 9, 10, Pro 2014, 11, 11 Pro