The preinstalled Samba server on both Cacko and standard Sharp ROM proves to be notoriously slow. This is mostly due to the strict syncing that’s enforced in the smb.conf – probably to avoid data loss. IMHO, it’s rather safe to disable this behavior and in turn get a nice speed bump. Here is how to do that:
On Cacko first delete the default link to the ROM copy of smb.conf:

sudo rm /etc/samba/smb.conf

Now, copy over from ROM and modify the copy:

sudo cp /usr/lib.rom/samba/smb.conf /etc/samba/smb.conf
sudo mcedit /etc/samba/smb.conf

Comment out lines

strict sync = yes
sync always = yes

Change the socket options line to

socket options = TCP_NODELAY IPTOS_LOWDELAY SO_KEEPALIVE SO_RCVBUF=131072 SO_SNDBUF=131072

Please remember to reconnect the mounted samba share on your desktop system.
In my case the transfer rate on my Buffalo 10Base-T CF-Card jumped from 350 KB/s to over 820 KB/s.