Both M4 and V4 can be installed to external runtimes.  In the days of DAZ installers and P6/7, you either had to install to the main Poser runtime or fool the installer by copying the Poser.exe to the external runtime folder.  The likely problem is you need to initialize M4.  In the libraries folder of whatever runtime you install the figure to, you will find a folder labelled !DAZ.  Inside will be a .bat folder.  Run the bat folder to initialize.  This should fix the problems.