Some simple questions about ardour and basic(?) audio tasks

Hello,

I am fairly new to Ardour but have looked over the online manuals.
Whenever I import audio I get inputs twice the amount of tracks that I imported.
(A stereo track gives me 4, mono two…)
Any idea why?
Am I doing something wrong? Or missing some interetsing point?
Is tehre some online info on this?

How would I split the audio into center, left and right parts?
Use M-S decode first, but then split the right and left audio?
Or rather: could I split up the audio, based on direction somehow? (say: center plus 30 degrees left/right is M, the rest is L or R)
And/or reassemble and manipulate the apparent direction where the audio is coming from?
(like on Waves’ stereo shuffler or what teh name of the plugin is)

Any ideas, tips?

J