Get Excel To Open MS Project File And Then Run Project Macro On It

I am trying to get excel to open a MS Project file and then run a project macro on it.

What is happen is that when I run my code it works, and then excels VBA window freezes up and the run arrow goes away, and if I try to open project I just get a chiming noise and it won't open.

For now I have to select the MS Project file from a directory, but in the future I would like it to go through the folder and open all of the file in the folder

EXCEL CODE
Sub ImportMSProject()
Dim FileToOpen
Dim mpApp As MSProject.Application
Dim prjmacro As Object
'Identify the File to Open - START
FileToOpen = Application.GetOpenFilename("Microsoft Project Files (*.mpp), *.mpp")
If FileToOpen = False Then
Exit Sub
End If
'Identify the File to Open - END

[code].....