Using DLL functions in Quattro Pro ??

I wrote the following DLL to test
but quatro will give an Error Function not Found

does anyone has any ideas how to write an DLL for Quattro Pro

Thanks
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Library Dlltest;

Function Test(Val:Extended):Extended;Export;
Begin
  Result:=Val*2;
End;

Exports
  Test Index 1;

begin
end.

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In Quattro Pro Cel   @DLLTEST.TEST(10)  > Error Function not Found