The reason why long filenames would not show on my FAT USB flash disk at least, was because the 2GB USB flash disk was factory default formatted as FAT16, I have two different brand 2GB USB sticks that are like this, it seems to be quite normal to format them as FAT16 if they are 2GB or less in capacity.
Reformatting the device as FAT32 did show long filenames, so I can use the device properly now. It would be nice if in the future if I can still use Ext2 or Ext3, but for now this will do.
It may still be a bug however, because classic Foxboard firmware does show long filenames on FAT16 USB flash disks, and so does my Ubuntu desktop PC, just not CrisOS, but at least I know that I can work around this issue by having my usb stick reformatted as FAT32.
The other 2 bugs I mentioned in my previous post are still standing and haven't changed for me.