Terrible Appearance/formatting In Sibelius V7

I have imported a MIDI file into Sibelius, and it's done a horrendous job with regard to note placement. (see image). It's a full orchestra and 30 pages, and every single bar is like the image, or worse, with the space between the notes wildly variant. I'm going to have to adjust every bar by hand!

I would expect there to be variation in beam length in eigth notes IF there are sixteenth notes elsewhere in the score on the same beat, but there are not. It seems totally ramdom. Does anyone know why this is happening and how I can fix it? Some setting somewhere I hope? I hope.

Thanks

I found the command. I would think the program would do this by default ... :veryunsure: