I picked up an issue with two of the link targets in all the tools listed in the test script, with the exception of 'Resources - HTML page' which works as expected.
The target is being reset to (_blank) after Post / Save for <not set> and <popup window> - so CK Editor looks like it has saved your selection after clicking OK, but when you save and then Edit again, the target has changed:
<not set> resets to (_blank)
<popup window> resets to (_blank)
Steps to reproduce:
1. Create an Assignment
2. In Assignment Instructions, click Link button
3. Choose Link Type 'URL'
4. Enter URL e.g. www.google.co.za/
5. Click Target tab
6. Leave default target as <not set>
7. Click OK
8. Right-click on the link, you just created, choose Edit Link, and verify your settings are still there, and you can also check that the HTML source looks something like e.g:
9. Click Post
10. In the Assignment list, again edit the same assignment
11. Click the Source button and check the HTML source after the save which shows that the the target has since changed to _blank: e.g.
<a href="http://www.google.co.za/" target="_blank">http://www.google.co.za/</a>_this_is_the_not_set_example</p>
12. You can also do this by right-clicking the URL and going into the Target tab
Follow the same steps for the <popup window> target...
Should look like this after Post:
<a href="http://www.google.co.za/" onclick="window.open(this.href, '', 'resizable=no,status=no,location=no,toolbar=no,menubar=no,fullscreen=no,scrollbars=no,dependent=no'); return false;">http://www.google.co.za/</a>_this_is_the_popup_window_example</p>
However it looks like this after Post:
<a href="http://www.google.co.za/" target="_blank">http://www.google.co.za/</a>_this_is_the_popup_window_example</p>