I wrote a long post about my problem and I think I accidently closed the tab (Why didn't it warn me? :/)
Anyway, I'll just write briefly. I installed a new awesome theme and got it working after hard work. Everything's running fine! Except of course, the 'Add Media', 'Add Link' and the 'HTML Editor'.
And yes, I read the 'Troubleshooting WordPress 3.5 Master List' and I did everything. And yes, the DEBUG thing DOES fix the Add Media and Editor, but I have to double-click the 'Add link', but then the screen goes grey and the box appears WAY in the bottom-left of the screen and I can't close it with the 'Cancel' button.
So, I turn off the DEBUG thing and as expected, the problem comes back. Instead of doing everything, can you please tell me simply how to force the theme to use WordPress's own jQuery instead of instead using its own?
I'll very grateful!