Well if you copy pasted that macro in you have a couple spelling problems and a formatting problem
Here it is corrected with the corrections in bold and below that is a copy paste friendly version.
/cast [target=focustarget,mod:shift] chain lightning; [target=focustarget,nomod] lightning bolt
Code:
/cast [target=focustarget,mod:shift] chain lightning; [target=focustarget,nomod] lightning bolt
You can't see it with the bolding but the separator in the parameters block is a comma (,) not a period (.)
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