Form not displaying in release version

Hi Folks,

I have a very perplexing problem at hand. I have developed an Excel addin in VS2010 which displays various of forms when a button is clicked on the ribbon. When I click a particular button on the development machine all works well. The problem only occurs with the deployed version of the software where when I click the button nothing happens!! The problem is further complicated by the fact that all other forms in the deployed version display as they should. I use the following simple code in ribbon.vb to display the form:

Private Sub btnCorrelations_Click(sender As Object, e As Microsoft.Office.Tools.Ribbon.RibbonControlEventArgs) Handles btnCorrelations.Click
    Dim DisplayForm As New frmCorrelation
    DisplayForm.ShowDialog()
End Sub

Related to this issue is the following. When I try to create a new button in a Ribbon Gallery I get the following error.

After clicking OK the new button is created anyway (called btnTest).

Can anyone suggest what may be going on here and how I might be able to resolve the issue?

Thanks

Bernie

Bernie