Adeptus Evangelion

I'll be DMing a game of Adeptus Evangelion tomorrow, though I have played Dark Heresy, I've never ran a game in it.
Though I do have experience DMing DnD 3.5.
Any last minute tips you fa/tg/uys can offer?

Don't just beeline straight to the objective even though you can. Try to keep combat every 2-3 sessions because it will eat up the WHOLE session. Schoolgirl drama?

It is a good idea that went horribly wrong, because Dark Heresy's rule-set isn't suited for it at all.
Not that I have a better recommendation, but you will have to hack another system or to make your own if you want this to work.

school ork drama?

The nonfight sessions have always been more enjoyable than the fights, in my opinion. Hopefully your players made characters that will interact interestingly together (and won't just ignore each other). Interesting doesn't necessarily mean positively.
OD is a pain in the ass to manage. It's like running two games at once that happen to meet up every so often. If you have an OD, it might be best to do their solo stuff at a different time entirely. Don't leave them out. Don't autoveto any crazy plans they have, either. They don't get to do that much.
Don't throw angels with TB 8 at early groups. I don't care what anything says, it's just not fun when the only things that work are furyfishing or dogpiling with knives. Use more wounds instead, also helps against crit. This is assuming 2.5 of course.

What's wrong with it?

Dark Heresy went wrong with it.
It was used because it had messy crit tables and insanity rules, but the rest of the rules are horribly ill-suited for anything Eva-related. And even those two things...
I'm not the person you were responding to, but I know this all to well. Far too well. I've been trying to work around DH for so long. So very long.

Hm, ok. I've only played with DH-rules once and that was in some Space marine version. The combat rules seemed ok.

Since you're running a DH version of AdEva, the dreaded words 'P-scale combat' might eventually come up. There's always complaints about that.
If you want it to happen, that's what you want for your game and you shouldn't have to worry about any of the below.
If you don't, there's ways around it, to various degrees depending on just HOW much you don't want it.
For one, don't let kids have guns. And kitchen knives aren't real weapons.
Trained professionals aren't going to be people with 30s and 35s in all stats and a few combat talents - if the children have high stats and a bunch of stuff, so will the adults. And, usually, backup.
If that's not enough for the feel you're going for, have the weapon proficiencies only apply to E-scale weaponry. Taking a hugeass penalty while the people you're trying to fight aren't makes things much harder.
Unfortunately, some people just can't stop being murderhobos. One and two are usually sufficient, use three only to say 'you will never win combat outside of your Eva and I don't want you even trying'

Ok since DH is clearly a poor choice for Eva, what would those here recommend?