无法在报表管理器中看到子报表

I've been following this tutorial (lesson 6) in order to build and deploy a sample report with an embedded subreport which reads its parameters' values from the parent report. This subreport is embedded in one of the group rows of the report's table, and both share the same datasource. Additionally, detail rows appear collapsed until the user presses the (+) button for each group of data in the table. (lesson 6) in