I understand the import file part, but every time I make and import, it puts all the instruments in one track. How I divide the instruments, so I can asign a difrent synthetizer sound to every instrument ? Or How can I open the file with all the instruments tracks ?
It can be done however it is time consuming and fiddly because you need to determine which channels are active, this could be as many as 16, and then seperate them out.
Import the midi onto the first track - double click the midi object on the track - this will open the MIDI Editor
Select Options, Midi channel filter
Select all channels except channel 1
Select all the note objects (Ctrl+A) in the Midi Editor and delete them
Select Options MIDI Channel Filter again and select All Active to enable the sound
Close the MIDI Editor to return to the timeline
Repeat steps 1 to 6 except use the next track and select all channels except the channel you require
Repeat for all the remaining channels.
You should now have 16 midi tracks each with a single channel on them, in sequence double click each one to see which has notes - if one track/channel is empty then you can delete it.