MusE can export SMF 0 or SMF 1 midi files,
which can then be imported into another application.
MusE will export all tempo changes and key signatures,
as well as markers and other meta events, including
specific user-added meta events.
Should work OK.
If there are still problems, running or exporting, feel free
to ask either here or in the mailing lists, or even file a
bug report if warranted. We can help.