Yes, it works fine.
However, it does not work in rc15 when the same description in the template which specified in the page attribute of the Navigator. In rc6, it works even in this case.
setActiveIndex worked, sorry.
<ons-navigator id="myNavigator" page="page.html"></ons-navigator>
<ons-template id="page.html">
<ons-carousel id="crsl" style="height: 400px; width: 400px" initial-index="1" swipeable overscrollable auto-scroll>
<ons-carousel-item>
Carousel Item 1
<ons-button onclick="document.getElementById('crsl').setActiveIndex(1);">Click to Change</ons-button>
</ons-carousel-item>
<ons-carousel-item>
Carousel Item 2
<ons-button onclick="document.getElementById('crsl').setActiveIndex(0);">Click to Change</ons-button>
</ons-carousel-item>
</ons-carousel>
</ons-template>