Thanks a lot for the quick help!! But only a part of our problem is solved... The video-countdown (reminder+micro) remains, but the textelements (calibration) still disappear. Here's what it looks like now (relevant parts):
<text calibration>
/ numitems = 15
/ items = calibration
/ select = sequence
/ fontstyle = ("Arial", 8%, true, false, false, false, 5, 0)
/ valign = center
/ halign = center
/ txcolor = (0, 0, 0)
/ txbgcolor = (230,230,230)
</text>
<trial calibration>
/ stimulusframes = [1=calibration, micro, reminder]
/ inputdevice = voicerecord
/ responseinterrupt = trial
/ trialduration = 15200
</trial>
<item calibration>
/1 = " OTTO~r~rStimmlage: neutral"
/2 = " OTTO~r~rStimmlage: hoch"
/3 = " OTTO~r~rStimmlage: Noch höher"
/4 = " OTTO~r~rStimmlage: tief"
/5 = " OTTO~r~rStimmlage: Noch tiefer"
/6 = " OTTO~r~rLautstärke: laut"
/7 = " OTTO~r~rLautstärke: noch lauter"
/8 = " OTTO~r~rLautstärke: leise"
/9 = " OTTO~r~rLautstärke: noch leiser"
/10 = " OTTO~r~rFreude"
/11 = " OTTO~r~rTrauer"
/12 = " OTTO~r~rÄrger"
/13 = " OTTO~r~rÜberraschung"
/14 = " OTTO~r~rAngst"
/15 = " OTTO~r~rEkel"
</item>
screenshot: https://www.dropbox.com/s/aq7va43z4ji6e8y/3.jpg