MIDI out from GarageBand

Hello, I'm trying to play a MIDI keyboard sending it a MIDI file from GarageBand. I know that GB doesn't provide this feature, but some years ago I found (using an older GB version, the 4.1.2) the MidiO driver, that allowed the output of MIDI signals from GB and made possible to replace the GB's internal voices with those provided by my keyboard.

Now I'm trying to do the same with the current GB version installed on my iMac (10.4.8), but I see no sign of life from MidiO inside GB. Unfortunately this MidiO seems to have been almost disappeared from Internet: almost no links referring to it, and no answer from almost all of them! I only found one site allowing to download it, but it's still the same 1.3 version I already had some years ago!

I tried to install it (copying the MidiO.component in /Library/Audio/Plug-Ins/Components) but with no success at all: the old GarageBand '08 recognized the presence of the MidiO driver, the 10.4.8 absolutely not!

Some questions from me here:

• Is there any driver that can provide the MidiO feature?
• If not, is there a newer version of MidiO available?
• Is there any missing step in the installation of this driver in order to activate it?
• last question: is there any free sequencer running on macOS that can drive an external MIDI keyboard?

Thanks for the help,

Ivan (Milan, Italy)