Cannot convert type error using C# CampaignMonitorAPIWrapper dll

I am using the C# wrapper dll, VisualStudio 2005.  The following does not compile:

Result<List<Campaign>> result = Client.GetCampaigns(m_apiKey, m_clientId);

Nor does:

Result<List<Campaign>> result = (Result<List<Campaign>>)Client.GetCampaigns(m_apiKey, m_clientId) as Result<List<Campaign>>;

The error is "Cannot convert type 'CampaignMonitorAPIWrapper.Result<System.Collections.Generic.List<CampaignMonitorAPIWrapper.Campaign>> to CampaignMonitorAPIWrapper.Result<System.Collections.Generic.List<CampaignMonitorAPIWrapper.Campaign>>'

I have not been able to download the sample code to see if there is any indication what I am doing wrong.

Any help?

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