I have found a bug.

I had to uninstall the pluging using the method you gave above.

I've re installed the product and when I go to set the permissions for each user group, the option is not visable. The yes/no boxes are still there.

Check the screenshot ive attached.

:( this is still not working for me!!!

I have uninstalled, then reinstalled. Made sure all the showthread template edits are correct. Uploaded all of the files...

I had the old version installed and it worked perfectly. This new version doesnt work at all for me now.

The options to mark the thread as solved doesnt appear in the Thread Tools.

Ah yeah I see it now. Thanks :) Marked as Installed
EDIT: Am I right in thinking that if I give registered users permissions to Mark threads as Solved, they can only mark their own threads as solved? Or can they mark any thread as solved?
Thanks in advance.

I used to use the old version of this and im sure its still the same. A registered user can only mark their own threads as solved. No one elses. Admins can mark any threads as solved though..

Thanks for this.
Any moderators that moderate that forum can mark them solved too, am I right?

Yes. But you do need to set their permissions first.

Well, for me it almost works. When I mark thread as solved, it become solved, I can filter display to see solved threads, but title reminds the same, witout the visible [SOLVED] in front.
Any help?

Marked as installed

This is how the new version works. It uses a thread prefix rather than changing the URL.

No idea why, but it isn't working for me at all. I can find it in vBulletin options to turn it on...it is on. However, in usergroups options it is simply not there. However, there is a blank yes/no radio option but no text to the left to say what it is..I turned it on to see if that would work and it still didn't help..nothing shows up at all.

I completely uninstalled the first version of mod I had before installing this one as well.

Honestly guys, I don't see how you are having these problems. For me it works fine, along with others I've had test it. The blank option to me makes no sense, I didn't change that in the xml, however - both of you try this for me:

Go to yourforum.com/admincp/index.php?do=buildbitfields

Check the usergroup permissions, re-save them.

And see if that works for you.

I mean really, not THAT much has changed since the old version.