Let this be a lesson to all the cIOSCORP users out there, cIOSCORP screws people up!
-well, i hate the bring the bearer of bad news, but without bootmii, preloader or homebrew, there is no way (as far as I know) to install a sane IOS via wad manager or dopIOS.
-what confuses me is that updating to 4.2 did not replace your IOSs (and effectively remove cIOSCORP). I would try updating again (if possible), it should update your IOSs, allowing you to run hackmii installer. If you can't update via nintendo because ur already at 4.2.... u may have to wait until a 4.3 update to remove cIOSCORP and rehack ur wii. The only other solution would be getting a mod chip... but ew... who wants a mod chip?
Again, these are my thoughts, not facts, but i'm confident in them... so good luck.