@skhms could you edit the resource to officially list the add-on as 1.3- and 1.4-compatible in the Overview tab? I was actually going to make my own until I found out yours works perfectly well. I think people might be turned off from downloading it because the Overview tab says it just supports XF 1.2.
Also, the add-on's title in the admin panel add-on list is "SK Mark Thread as Thread" which should be "SK Mark Thread as Read", just pointing that out.
I can't get this to work properly with XenForo 1.4.3. All of the files have been uploaded to my server, I installed the xml file and nothing appears next to any unread threads. Am I missing an option somewhere in the ACP to get it working?
But you do need to hover over the thread for the 'Mark as Thread' link to appear. Just like you need to hover for the page navigation to appear in a thread list.
Does the 'Mark Threads as Read' option shows up in list with actions on the admin panel when you select a thread?
Besides that I guess that you can check if the automatic template edits worked.
Perhaps you need to add them manually if you've made some other changes to the template.