Dear all
First, sorry for my english, i will do my best.
My problem is quite simple to understand. I tried to create some Ibooks with math equation for my students but i have some display problems.

On the left, in ibooks author equations display right. On the right, in ibooks, all my equations display wrong.
I tried everything, sometimes it works for a few hours and then it display again wrong.
Some short equation seems to stay right.
Regards