Sheila, I run all of my purchased content from external runtimes and don't have any problems.  I don't think you need to install anything to the P7 runtimes.  All of my external runtimes are out on a 250 Gb USB drive and I don't have any troubles with any of them (and I've got a lot of them right now).

Hugz from Phoenix, USA

Victoria

Remember, sometimes the dragon wins. Correction: MOST times.