Raven populate form with "old values" and edit

So I'm trying to create a simple add/edit "person" process using Raven. I can add a person with:

    {{ raven:form formset="person" }}
        <input type="text" name="title" value="{{ value:title }}" />
        <button>Create</button>
    {{ /raven:form }}

and then list the entries:

    <ul>
        {{ entries:listing folder="people" }}
            <li><a href="{{ url }}">{{ title }}</a></li>
        {{ /entries:listing }}
    </ul>

All seems ok except when I select an entry from the list (takes me to a new page), I cannot seem to populate the Raven form with that entries old values:

    {{ raven:form formset="person" }}
        <input type="text" name="title" value="{{ old_value:title }}" />
        <button>Update</button>
    {{ /raven:form }}

I'm not sure if Raven can do this, or if I'm missing a step. I guess I would need to pass in the context of which record to get the form values from but the ability to "edit" a form submit and re-save doesn't seem to be documented? Essentially, I'm trying to replicate something similar to the Update member profile form with Raven but not sure if its possible? - Hoping so after just purchasing it...

At the minute I'm stuck being able to save and list, but not edit an existing entry.

Any help please?