Can't finish Carrack's quest

[aerokid]

Hi, there!

I am now in Chap 6, and it's likely too late to initiate Carrack's quest.
I've not visited the booter or prison to leave as many quests as possible for Imoen.

Question 1 :  Is there anyway to get the quest? (editing global or using createcreature....)
                   I tried create D0qpgude.cre ... but the message said I was too late.
                  
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So, I loaded a savefile before Chapter 4, and got the quest.
I met Carrack(armed) in the Bridge District and killed those 3 thieves.
On entering the house. Carrack said nothing, so I initiated dialogue.

What he says is "Die, Scum" only.  

Question 2:  If this is a bug, is there no other way than reinstallling?

Question 3: I couldn't find no special global thing about this quest.  Is this OK?


Thank you everyone in advance.
 also the creator for his splendid job.