diff --git a/melodic.tcl b/melodic.tcl
index 6163c25c1693a6859257fde529563248dda94a26..217b934a7387ea54cfe6ab3161f1fdd7d6abd9a3 100644
--- a/melodic.tcl
+++ b/melodic.tcl
@@ -255,7 +255,7 @@ balloonhelp_for $w.dim "In order to avoid overfitting, Melodic will attempt to e
 components from the data using Bayesian estimators for the model 
 order and use PCA to reduce the data prior to the IC estimation."
 
-set fmri(dim) 0
+set fmri(dim) 1
 LabelSpinBox $w.dim.n -label "Output components" -textvariable fmri(dim) -range { 1 200000 1}
 
 #}}}
@@ -336,7 +336,7 @@ pack $w.varnorm $w.dim  $w.thresh $w.ostats $w.report -in $fmri(melodicf) -ancho
         -side left -expand yes -padx 3 -pady 10 -fill y
  
     pack $w.f $w.btns -expand yes -fill both
-$w.nb raise data
+    $w.nb raise data
 #}}}
 }
 
@@ -351,6 +351,7 @@ proc melodic2:updatest { w } {
     } else {
 	pack $w.st_file -in $fmri(stf) -side left -padx 5
     }
+    $w.nb compute_size
 }
 
 #}}}
@@ -379,6 +380,7 @@ proc melodic2:updatedim { w } {
     } else {
 	pack $w.dim.n -in $w.dim -side left -padx 5 -after $w.dim.yn
     }
+    $w.nb compute_size
 }
 
 #}}}