Hi,
no, during this time frame I have'n installed any other air application.
Another thing: when I see version 3.5 Adobe Air on Windows Control Panel, I cannot remove it: appear un error "... Impossible remove ... contact system administrator". So I have found a Microsoft patch in Internet, with this patch I can remove Adobe Air 3.5.
So now I have uninstalled Air 3.5 with the patch and after I have installed version 28 and now I wait if this installatrion is stable (before I install Air 28 on Air 3.5 without disinstall 3.5)