Recording MIDI with external clock

How to?

I decided to try to recorde the automatic accompaniement from my Casio WK-1800 keyboard as MIDI to be able to modify some parts in n-Track, but I have had no success.

The keyboard does not support external clock, so I tried to configure n-Track for external MIDI clock (Input-MIDI Clock-Enable), I configure a sufficient amount of MIDI tracks and press record. The record button starts blinking and a notice appears ‘Waiting for incoming sync signal’, but when I press start on the keyboard the record button stops blinking (inactivated) and nothing more happens. What am I doing wrong?

I did also try with an ancient Cakewalk Pro from the beginning of the 90’s and with it I could record using the keybords clock, but surely it should be possible with n-Track also?