The List Item token allows you to create numbering like this:
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You will be able to restart the numbering at the (a), (b), (c) level, without resetting the 1.1, 1.2, 1.3 level numbering. 

First, make a special token at the start of your flow, the label should be List Item and the value will be |||LISTITEM-lowerLetter,(%1)|||

For each list, use your List Item token for each item in a paragraph point like this:
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For every List Item token occurring after each other, you'll get the (a) (b), (c) etc. The "lowerLetter,(%1)" text can be adjusted in the same way the reset tokens can to change your list numbering to (e.g.) upperRoman numbering etc.
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