Qtractor exporting invalid MIDI

[elkaro]

Hi folks, hope someone can help me because I don't get what's really going on.

I have a song created in Qtractor, 4 insttruments. Some tempo/key/time signatures changes here and there.
When I export the whole MIDI thing to load that in another DAW (basically I want to render the bass and acoustic guitar in a windows DAW with free plugins) the resulting MIDI file can't be opened properly elsewhere.

I mean, I can perfectly load the exported MIDI file in qtractor, but any other program fails.
Ardour manages to load the time map, but nothing else.

I've tried all available exporting options: By time, frames or BTT.
Any idea?

[rncbc]

it would help if you show us the said MIDI file

ps. Time, Frames or BTT options do not affect the export result whatsoever: they only serve for time display/entry format in the dialog.