Okay, let's back up a bit and try to sort this out.  Your first problem, I see that you were trying to install V4 using the installer designated for DAZStudio, the reason for your error message.  I am assuming that you inadvertantly used the DAZ Content installation to create the absolute path.  I recommend using Poser (All Files) for that trick. 

Your second problem is not a problem at all.  Those folders you see in Poses actually belong there; those are part of INJ/REM files created for Vicky.  DO NOT MOVE.  Now, you mentioned that you have no expressions in your library, however, I see that you have 41 files in !V3 Expressions INJ and !V3 Expressions REM.  When you say you have nothing, is it truly empty or are there icons with shrugging men?  This is important, because if it is the latter, what you are seeing are icon representations of rsr image files which are not longer supported by current Poser version.  You will need to convert those using an rsr to png conversion program found in the free section here at Rendo.

Now, those expression morphs will only introduce extra dials into your Parameters pallet, they will not automatically change the facial features.  And, btw, I discovered that V3 SAE already has expression morphs already built-in, no need to INJ those features.