Well, while there is probably something bigger wrong with your situation, the quickest fix for the thing would be to set the switch in the dialogue file so the right line appears.

Open Dullarse's dialogue file with Windows Notepad editor:

Assuming a default install it would be at C:\Program Files\Bethesda Softworks\SeaDogs\RESOURCE\DIALOGS\francis_dullarse_common.d

Scroll down to the section that starts with:

<N node_quest>

A few lines below that is the line about Suraknar, that's SUPPOSED to look like this:

<L link_ss,1,1,node_ss_1>
<T Francis, I heard you've got a new shipwright in town.>

Either you're going to encounter one of two things at this stage:

1.  The line's not there.  If it's not there, then the mod didn't install right.  Run the Installer, delete & reinstall the Suraknar mod & start another game.

Or

2.  That first line <L link_ss,1,1,node_ss_1>  has some zeros in it instead of one's, like:  <L link_ss,0,0,node_ss_1>.  If this is the case, start the game, load your save if necessary and get right next to Dullarse.  Swap out of the game into the windows desktop, and using Windows Notepad editor on the file, change the zeros to ones and save it.  Then swap back into the game and talk to Dullarse and the line will appear.

My bet is that #1 is your problem.  I'm thinking there's a messed up installation somewhere along the line.