Lull mez and charms - how do they work

[Dalmon]

Hi all, im a level 40 enchanters and with my self buff I can get my CHA to 196. I usually am grouped with friends in a trio of, ENC MNK SHM. and most of the time when we fight i use a charmed mob

I was curious as to how these 3 types of spells work in reguards to my CHA and to the rank of the spell.

What I know and believe is to be true that is ever 6 second my charmed mob can attempt to break it, based on his magic resist level, actual level, and my CHA.
Is this true?

it might also be worth mentioning that if I am going to keep a charmed for a bit, I tash the target as well as get it maloed from the SHM.

My other question is that, even though my CHA is high (or at least I consider it high) at 196, often mobs will resist my lulls, making so I would have to cast it 4-5 times before getting it to stick and it often dents my mana pool where rooting it could be more efficient. Im currently using level 20 Spell:calm to do the lulling and I have yet to pick up the level 39 Pacify.

Are the constant resists of my lull due to not using the highest rank I can get? and if this is the case how come I am still able to use my level 8 Spell: root effectively. Should i be using my newest rank of root as well?

any imput would be great thanks!