[quote="sanddurst"]Is it true that exalted shani placed in seventh house creates Rajyoga?

[/quote]
Sasha or Shasha mahapurusha yoga. For rajyoga two separate planets need to be involved and not one planet that happens to be lord of a kendra and trine (shani for libra for instance or mars for karkata lagna). In these two examples (4 and 7) the planet becomes a yogakaraka, though.
Mixing rajayogakaraka, yogakaraka and mahapurushayogakaraka planets into meaning the same thing is not something I would recommend in my humble view.