I updated my NW nights to 1.61. But I can't seem to get Lenton in Archaeologist Barracks to talk to me so I can complete the "A Troll lead trophy"? Can someone help me with this bug? He keeps fighting but wont talk to me.

Well if he's fighting you can't talk to him, you'll just get the "this object is too busy to talk right now" response. It's a pain but the only thing you can probably do is just keep clicking on him and try to start up the dialogue while he's in between blows.

I tried talking to him between his fights with the dummy but nothing....after I saved it and tried again I thought attacking him will make him stop the fight and talk. But no he died instead....so how am I going to finish that part of the sub-mission?...need help on this cause I got the troll head and paper already....

and he still dont talk to me about the quest...

It's bugging me alot, i finished the quest before it got all... crazy, i've tried talking to him after i got the expansions and patched but it doesn't work, :|

I'l check the official forums for anything about this, if there's no topic about it i'll post one.

Ok to help out more I found out how to fix this bug on 1.61. I saw this post on the bioware forum. You have to be in DebugMode to use this part. After this command type dm_setfactiondefender click on lenton. Do this couple time then he will stop and talk to you. Then if you have the troll head already before he talks to you about the mission just click back on him after your got your quest from him and tell him you got the troll head and you will complete the quest. Then you can turn off the debugmode. This help me complete the troll quest.

And how does one get into debugmode? Is that where you type DebugMode=1 in the program options heading in the NWN's folder?

To enter DebugMode in game hit the ~ button next to the one and it will open a line to type on then type DebugMode 1 and it should work.

Well there are plenty of web game site that tells you how to implement the DebugMode into the nwn.ini files. Here the lowdown then.
Go to the directory where you have Neverwinter directory. Here I just post what I did change.
[Game Options]
Memory Level=1
Memory Access=1
Debug Mode=1
Then to finish the Lenton Troll quest you use the "~" key when your in the game to start the debug mode but dont forget you have to type "DebugMode =1" to debug. Remember you must always use the "~" key for each command you type. The one to use to make Lenton stop attacking the dummy to finish the quest assuming you got the troll head ahead before talking to lention "I think in patch 1.61 this is a bug". Type "~" then dm_setfactiondefender <enter> and click on lenton do this 2-3 times for me. Then he will stop and talk to you and tell you about the quest and then if you have the head dont tell him yet finish what he wasnts you do to and then click back on him and then tell him you have the troll head. Whoppeedo...now you finish the quest..I know..this cause I read it from the bioware forum and some posted this debug feature. If they havent done so I be still trying to finish this quest. I hope this helps clarify for those who are frustrated by bioware new bug.

I was unable to make the above mentioned technique work, probably because I was doing it incorrectly, I'm sure.

However, ArtEChoke gave me the idea to attack Lenton and cast "Charm Person" on him. And it worked! Lenton has very low hp so I attacked him with no weapon and immediately cast charm person on him. I had to do it twice, however, because the first time, he went right back to attacking the dummy. The second time it worked perfectly.

Just another tip, if this particular quest gets anyone stuck.