It's happening again in 3.5.9. This time at the new ByteReader since File is not available in Metro.
Here is how I fixed it:
static public ByteReader Open (string path)
{
throw new System.NotImplementedException();
//FileStream fs = File.OpenRead(path);
//if (fs != null)
//{
// fs.Seek(0, SeekOrigin.End);
// byte[] buffer = new byte[fs.Position];
// fs.Seek(0, SeekOrigin.Begin);
// fs.Read(buffer, 0, buffer.Length);
// fs.Close();
// return new ByteReader(buffer);
//}
//return null;
}
Perhaps you could setup a batch file to try out all the builds using the unity command line:
https://docs.unity3d.com/Documentation/Manual/CommandLineArguments.htmlThen you could find these kinds of build errors easily before releasing.