There is a slightly newer version of the tlk (copaptlk_4_9a.tlk) file used to play on the Avlis servers due to development changes. To update, simply follow one of the download links below, unzip the copaptlk_4_9a.tlk file and place a copy into your NWN directory inside the tlk folder.
This new file can be found directly here for download:
https://neverwintervault.org/sites/neve ... k_4_9a.zip
A link can also be found on the Wiki under Avlis Needed files page here: