Category Nav tag with control over the depth that {% children %} goes

Question

Looking at the docs, i can see that the category {% nav %} loop uses the categoryGroup as the starting point. But, i want the first top level category within the category group as the starting point.

So, i want to do something like:

{% set categories = craft.categories.slug('my-first-top-level-cat).first().getChildren() %}

{% nav category in categories %}
<ul>
    <li>
        {{ category.title }}
    </li>
</ul>
 {% ifchildren %}

   {% children %}

 {% endifchildren %}
{% endnav %}

But, doing this only returns the top level, no sub levels.

Also, i want to be able to limit the amount of children output as the there are a few sub trees.

Answer 1

i did {% set categories = craft.categories.descendantOf(1066) %}

And then i did

{% nav category in categories.level(2) %} {% endnav %}

Always get the answer myself just after i post these damn things.