I believe that the 2 skills in the single slots are cast immediately after the Guardian is summoned (provided that there is a target, obviously). Following these two skills will be the 4 skills in the repetitive slots, cast according to their order (first slot skill is cast first, last slot skill cast last). The Guardian then circulates through these skills again and again, assuming that the skill(s) is not in cool down.
Personally I like putting debuffers first (i.e. Shield Breaker), then Skunk Pouch last. This is because I generally play on close-rangers, so getting the greatest immobilized-boss-time where I receive no attacks is important to me. But I think it's really up to your preference since the skills will be cast again and again. I have no idea if there's some sort of 'strategy' with this :c
To answer your second question: I have never seen my Guardian cure me or anyone else for that matter. Usually when it cures one of my guildies, everyone would make a big deal out of it since it's such a rare thing - and this has only happened twice in my two years of playing Trickster. Your HP has to be really low for Cure to be activated, and I'd rather use pots to save myself rather than to count on my Sephirens :c
| Ceciel | Aerilynn | Ferisu | Aquillo |
+Rep if I helped please~