Asset Insertion

asset_insertion.mtml

<MTUnless regex_replace="/\t/g","" strip_linefeeds="1">
<mt:if tag="AssetType" eq="image">
	<mt:setvarblock name="href"><mt:if name="image_width" gt="640"><mt:AssetThumbnailURL width="640"><mt:else><mt:var name="a_href"></mt:if></mt:setvarblock>
	<div class="article-image" style="text-align: left; width: <mt:var name="img_width">px;<mt:If name="align" eq="left"> float: left; margin-right: 10px;</mt:If><mt:If name="align" eq="right"> float: right; margin-left: 10px;</mt:If><mt:If name="align" eq="center"> margin: 0px auto;</mt:If>">
		<mt:var name="form_tag">
			<a rel="lightbox" href="<mt:var name="href">" title="<mt:if name="caption"><mt:var name="caption" escape="html"> </mt:if>(click to enlarge)"><mt:var name="img_tag"></a>
			<mt:if name="description"><p class="credit"><mt:var name="description"></p></mt:if>
			<mt:if var="caption" ne=""><p class="caption"><mt:var name="caption"></p></mt:if>
		<mt:if name="enclose"></form></mt:if>
	</div>
<mt:else><mt:var name="upload_html"></mt:if>
</MTUnless>

Asset Insertion Template is in AssetContext of InsertedAsset.
Remove <mt:Asset id="$asset_id">.