If you wish **non-**aligned partitions you have to specify a variance, something I’ve never investigated, and may not be possible unless using a non-standard “geometry” (not using the modern standard 64 heads & 32 sectors). The app defaults to the ancient 255 heads & 63 sectors “geometry” convention for disks with no partition table.
AFAIK, the only way to get a size in megabytes is to first convert to mebibytes and then specify the converted number. Using the create menu, I see no option to select sizing units. The tabled result sizes are always stated in MiB when I use it. This is not a subject I’ve ever investigated, so I could well be wrong.
Assuming you do not wish to do the work using its menu system, the target is the second disk in the system (change disk number appropriately if not), and the target disk has no existing partition table, this is the command line template:
0a: disk 2
0b: geo ? 64 32
1: cr pri linux 400 -a:1,c -f:#
2: cr pri ntfs 250000 -f:#
3: cr pri linux 150000 -f:#
4: N/A
5: cr log swap 8400 -f:#
6: cr log fat32 -f:#
For -f:#, substitute for # the number in the table column 1 shown by the last action that identifies the freespace in which to create new partition. If there is no freespace on disk 1, then -f:# can be omitted. It also can be omitted if the target is the first available freespace of adequate size.
-a:1,c above means start the partition at the first sector of the second “cylinder” (cylinder 1, starting from 0), which with standard 64 head 32 sectors per track “geometry” causes proper alignment with 4k internal sector size when applicable, leaving Grub ample room to install on the first “cylinder”, same as any of the current FOSS partitioning tools.
linux above equates to 0x83 (aka LinuxNative), which may be used instead.
ntfs above equates to 0x07, which may be used instead.
swap above equates to 0x82, which may be used instead.
what fat32 will equate to depends on size and location on disk, but typically 0x0B or 0x0C.
