I think I found part of the problem.

After partitioning, i rebooted, then

sudo gainroot
sfdisk -ls

and got the following results:

/home/user # sfdisk -ls
/dev/mmcblk0: 15694336

Disk /dev/mmcblk0: 490448 cylinders, 4 heads, 16 sectors/track
Units = cylinders of 32768 bytes, blocks of 1024 bytes, counting from 0

Device Boot Start End #cyls #blocks Id System
/dev/mmcblk0p1 32 448031 448000 14336000 c W95 FAT32 (LBA)
/dev/mmcblk0p2 0+ 31 32- 1023+ 83 Linux
/dev/mmcblk0p3 448032 490447 42416 1357312 83 Linux
/dev/mmcblk0p4 0 - 0 0 0 Empty
total: 15694336 blocks

For some strange reason, the 1GB I allocated for the Linux partition for the bootspace ended up being mmcblk0p3 instead of mmcblk0p2 as I thought.

How do I designate p03 to be the default bootspace?