Problem Deploying Custom Report Item. Items Shows In Preview Screen In VS, But Not In Server Deployed Report

I have developed a custom report item that works fine in design and preview mode while in Visual Studio. I cannot get it to show up on my deployed reports. Here's what I have done so far:

1. Deployed the report using Visual Studio

2. updated the rsreportserver.config file with the following entry:

<ReportItems>
<ReportItem Name="PedigreeChart" Type="Uabr.Rap.PedigreeChart.PedigreeChartRenderer, Uabr.Rap.PedigreeChart" />
</ReportItems>

3. Updated the rssrvpolicy.config file with the following entry.

<CodeGroup
class="UnionCodeGroup"
version="1"
PermissionSetName="FullTrust"
Description="This code group grants Uabr.Rap.PedigreeChart.dll FUllTrust permission. ">
<IMembershipCondition
class="UrlMembershipCondition"
version="1"
Url="C:Program FilesMicrosoft SQL ServerMSSQL.3Reporting ServicesReportServerinUabr.Rap.PedigreeChart.dll" />
</CodeGroup>

I've also tried using the StrongNameMembershipCondition with no better results.

4. The dll and its dependencies are copied to the bin directory of the report server.

5. When I load a report with this custom report item on it, the report loads fine with no errors or warnings in the log file (even with verbose tracing). The area where the custom item should be is just white. It's almost like Reporting Services isn't registering the item correctly.

This is particularly frustrating because the report works fine in Visual Studio - apparently I configured that correctly. Any suggestions would be greatly appreciated. I'm stumped.