Hi, there,
I think I have the similar problem here, is this resolve?
I installed ML in my 550D before, and it worked great, then I wanted to use my eye fi pro X2, so I uninstalled ML(set BOOTDSK flag in camera false) and inserted eye fi card into 550d, it said "no card in camera", but normal SD card works fine on 550D, and I tried eye fi card on my old digital camera, all function works fine.