Unable to import content with remote api

I'm able to load files into sheet just fine, but writer doesn't like it for some reason. Maybe it can't handle the large file size? It's about 1m. Here's my code:

<form target="_blank" action="http://export.writer.zoho.com/remotedoc.im?apikey=9e7a4165451bcb2f828cf1089e050e04&output=editor" id="frmZohoEdit" method="post">
<input type="hidden" value="123" id="txtZohoID" name="id"/>
<input type="hidden" value="http://dev.entrecore.com/sys/nl/ai.esp?cid=98ae845ecc2747abc9db3ab9e4510cdb&iid=108&taf=0&action=LoadEmailAttachment&id=214" id="txtZohoFileURL" name="url"/>
<input type="hidden" value="http://dev.entrecore.com/sys/nl/ai.esp?cid=98ae845ecc2747abc9db3ab9e4510cdb&iid=108&taf=0&action=SaveFromZoho&edit=123" id="txtZohoSaveURL" name="saveurl"/>

<input type="hidden" value="PayFuse User's Training Guide.doc" id="txtZohoFilename" name="filename"/>
<input type="hidden" value="doc" id="txtZohoFormat" name="format"/>
<input type="submit">
</form>