You could use a <$list> widget to manually display the top level *outside* the toc-selective-expandable, and then use toc-selective-expandable for the inner levels. Something like this:
<div class="tc-table-of-contents">
<$list filter="[tag[Layer1]]">
<$button class="tc-btn-invisible">{{$:/core/images/right-arrow}}</$button>
<$link><b><$text text=<<currentTiddler>>/></b></$link>
@@display:block;margin-left:1em; <$macrocall $name="toc-selective-expandable" tag=<<currentTiddler>>/>@@
</$list>
</div>
The result is that you *always* display the top level ("Layer1") items opened, while the inner levels behave as usual for the TOC macro (i.e., default to 'closed', click to expand).
Note: I did *some* layout formatting and styling to make it look mostly like the TOC at the top level, but you will want to adjust the formatting/styles to suit your needs.
enjoy,
-e
Eric Shulman
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