- It was a mistake! I didn't mean to open it! It was a mistake! You can all go to hell!

(jIQaghpu'! vIpoSmoHqangpu'be'! jIQaghpu'! ghe''or lujaH! Hoch!)

jIQaghpu'! vIpoSmoHpu' 'e' vIHechbe'! jIQaghpu'! ghe''or yIjaH!

Context makes it clear that she's talking to all of you. You don't need an explicit Hoch, nor does it really fit here.

- You solved the box. We came. Now you must come with us. Taste our pleasures.

(buq'Ir QapmeH Ho'DoS Datu'ta'; mapawpu'. DaH jutlhejnIS. belmeymaj DaSIQnIS).

buq'Ir Dapanpu'.

I don't know what "taste our pleasures" means, but if it's metaphorical in English, you might as well keep it metaphorical in Klingon.

belmaj tIwaH.

(crying)
- Please... go away and leave me alone!

(Saqoy'.. naDevvo' yIghoS, 'ej HIlon!)

naDevvo' peghoS

- Wait! Wait! Wait! Wait, please, wait!

(peloS! peloS! peloS! peloS, Saqoy', peloS!)

This would be an ideal time for clipped Klingon: loS! loS!

- No time for argument.

(maghoH; poH yap tu'lu'be').

yapbe' ghoHmeH poH.

- You've done it before, right?

(pa'logh, jaSHa' Suvangpu', qar'a'?)

Done what? I've never seen this film, so I don't know how vague this line is supposed to be.

You don't really need the pa'logh. The perfective and the adverbial are enough. You have acted similarly, right?

- Many, many times.

(jaSHa' mavangpu', 'ej ghIq mavangqa'pu', 'ej ghIq mavangqa'pu').

pIj!

- To a man called Frank Cotton?

(jaSHa' frank cotton loDvaD Suvangpu''a'?)

loDvaD Frank Cotton ponglu'bogh?

(female cenobite)
- Oh, yes.

(oh, HIja').

Just drop the oh when translating things like this. In English, it's just an intensifier. You can't intensify Klingon HIja' yes. In other cases, you might turn it into an appropriate suffix, like jutlhejbej Oh, you're coming with us! or bIrqu' Oh, was it cold!

- Supposing he had escaped us. What has that to do with you?

(vabDot maHvo' narghta'chugh, chay' Dubop wanI'vam?)

- I can... I can lead you to him! And you can take him back instead of me!

(vISammoHlaH.. tlhIHvaD ghaH vISammoHlaH! 'ej ghe''orDaq ghaH botlhap; tutlhap 'e' qa'!)

To reproduce the hesitation, I'd imagine how she's been talking about him, and do this: ghaH... tlhIHvaD ghaH vISammoHlaH! In your version, she's already worked out what she can do, so there's no reason for her to hesitate in saying the whole thing the first time. My way, she's searching for something to say about him, something they want to hear, so she starts with an object, ghaH, and then works out what she wants to say.

I'm not sure whether "take him back" is supposed to mean return him (tatlh) or take him when you go back (tlhap). Either way, you can say ghaH'e' him (instead of someone else) and leave it to context to imply the instead of me part.

ghaH'e' botatlhlaH! You can return him (instead of someone else, like me)!
SucheghDI', ghaH'e' botlhaplaH! When you return, you can take him (instead of someone else, like me)!

-- 
SuStel
http://trimboli.name