Hi Cyan,
I have had a good play about with this again now. I have beta-alt53 installed as cIOS 249 (Base 56), cIOS 250 (Base 57) and cIOS 251 (Base 58). If I run on cIOS 249 or 250, the drive will not mount, no matter if the Wii U drive in PORT 0 is connected or not, either during having the...