I haven't tried it in 3.4 but it works fine with 1.2. These are the events used for one of the missions: (‡ denotes a chained event)
•MSGL/AI: Delphi arrive 1-6 (standard event)
‡BF: Amenemhet (repeat count 1, chain delay 32)
‡BF Amenemhet 2 (repeat count 10, repeat interval 50, chain delay 1)
--when
----true
----fire-beam
------Amenemhet
------turret03
------Delphi
----fire-beam
------Amenemhet
------turret04
------Delphi
‡BF: Delphi (repeat count 10, repeat interval 50, chain delay 3)
--when
----true
----fire-beam
------Delphi
------turret20
------Amenemhet
----fire-beam
------Delphi
------turret26
------Amenemhet
Pretty standard stuff, but the two BF events only work once. It works fine if is-event-true-delay is used instead of the chains, so it is really not too much of a problem except for missions that have already been released.