I don't know if you can do anything with containers gotten from 'geif'. It works for books and keys, though.
If you hit the 'debug keys' button (bottom of the right column in the cheat menu window) to toggle them on, after you exit the cheat menu you can use Ctrl-# to spawn specific types of opponents. Copied from a
GOG topic;
Ctrl+Y = complete quest 'By The Book' (gold, EXP, loot choice)
Ctrl+A = stuck in loading screen
Ctrl+S = turn off sound
Ctrl+F = Load autosave
H or Ctrl+H = Hides UI (for nice menuless screenshots)
Ctrl+K = Removes all inventory items (including quest items)
Ctrl+L = Crash
Ctrl+Z = Toggle markers
Ctrl+X = Level up
Ctrl+C = Open battle tower storage
Ctrl+V = Open blank book
Ctrl+M = Mute
Ctrl+2 = Spawn Tribal Goblin Chief (level 4)
Ctrl+3 = Spawn Tribal Goblin Warrior (level 2)
Ctrl+4 = Spawn Tribal Goblin Ranger (level 4)
Ctrl+5 = Spawn Tribal Goblin Shaman (level 3)
Ctrl+6 = Spawn Tribal Goblin Healer (level 3)
Ctrl+7 = Spawn Zombie (level 40)
Ctrl+8 = Spawn Zombie (level 41)
Ctrl+9 = Spawn Zombie Jake (level 39)
Ctrl+0 = Spawn Troll (level 1)
Numpad 1 = Teleport to a higher point
Numpad 2 = Teleport forward (good chance of getting you stuck in geometry)
Ctrl+Num1 = Toggle 'HUD Text Output' text
Numpad 4 = Turn movement controls 45 degrees CCW (left becomes down and left)
Numpad 5 = Sync movement controls to normal
Numpad 6 = Turn movement controls 45 decrees CW (left becomes up and left)
Numpad 9 = Autosave
Ctrl+Num9 = Load autosave but with message stuck on screen