Welcome to the Forum:)
IMO, you can't Duplicate Characters. Only Props.
Select the Prop in Scene Manager while holding-down Ctrl Key, for the first Duplicate. If you want to Multi-Duplicate, Select the Original & Duplicate, while holding-down Ctrl Key & so-on.
Then Select the Move Tool (While still holding-down Ctrl Key). The Duplicate then appears in Scene Manager & Drag the Duplicate(s), while holding-down the Shift Key, to Postion it/them.
It's a bit fiddly & needs some practise.
BTW - iC5 has a new Multi-Duplicate Tool Feature.
I'll double-check the above in iC5, here, without using the Multi-Duplicate Tool.
Done - See Screenshot:

Anyone-else?.
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