When you create a new Gateway EMUNAND, the FSID in the partition table for EMUNAND data is 1Ch (Hidden LBA W95 FAT32), which some systems, especially some older mobile phones, still think that it is a valid FAT and try to mount and "fix" it, thus screwing everything up.
My suggestion is to change the FSID to DAh (Non-FS data), so those devices do not (mis-)detect that partition.
You may actually got a valid point here. I'm going to discuss this and think about it for a bit, alright? In the meantime, other opinions are welcome.
I have done it manually with Linux fdisk and it works as normal.
Disk /dev/sde: 29.7 GiB, 31914983424 bytes, 62333952 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x71c7099b
Device Boot Start End Sectors Size Id Type
/dev/sde1 1933312 62333951 60400640 28.8G c W95 FAT32 (LBA)
/dev/sde2 * 1 1931264 1931264 943M da Non-FS data
Partition table entries are not in disk order.
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You may actually got a valid point here. I'm going to discuss this and think about it for a bit, alright? In the meantime, other opinions are welcome.