Smith Micro says that it is not necessary to install DAZ Content in the main Runtime.

http://support.smithmicro.com/cs/smkb.cfg/php.exe/enduser/std_adp.php?p_faqid=2257

I've had no issue with V4 or her kin outside of the main Runtime (I put them in a folder named Characters).  You do have to fool the installer by creating a blank poser.exe as described in the faq, above.

You should be able to move your old python scripts from P7 to P8.  Python content almost always needs to be in the main Poser runtime.  Personally, I zip up the poserscripts folder before moving anything.  Be sure not to move anything in "DLLs" or "Lib".

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