Put a CF card (at least 128Mo) into you PC CF card reader, and as root, create 2 primary partitions on this card: the first one should be a FAT32 partition (type 0x0B) of approximatly 10Mo, and the second should be a EXT2 partition. Those partitions MUST be primary partitions (not extended) (they will be /dev/hda1 and /dev/hda2 in your future Linux system)

format those partitions

copy zImage file into the root of FAT32 partition. Unpack linexec archive into this partition.

unpack the Opie disk image into the EXT2 partition

unmount CF

plug it into your A620

Execute linexec.exe and enjoy !