ADDED   mttroot/mtt/lib/comp/compound/Bicausal/B2U/B2U_abg.fig
Index: mttroot/mtt/lib/comp/compound/Bicausal/B2U/B2U_abg.fig
==================================================================
--- /dev/null
+++ mttroot/mtt/lib/comp/compound/Bicausal/B2U/B2U_abg.fig
@@ -0,0 +1,43 @@
+#FIG 3.2  Produced by xfig version 3.2.5-alpha5
+Portrait
+Center
+Metric
+A4      
+100.00
+Single
+-2
+1200 2
+2 1 0 2 0 7 100 0 -1 0.000 0 0 -1 0 0 3
+	 1350 6525 2700 6525 2475 6750
+2 1 0 2 0 7 100 0 -1 0.000 0 0 -1 0 0 3
+	 2925 6300 2925 4950 3150 5175
+2 1 0 2 0 7 100 0 -1 0.000 0 0 -1 0 0 3
+	 3150 6525 4500 6525 4275 6750
+2 1 0 2 0 7 100 0 -1 0.000 0 0 -1 0 0 3
+	 4725 6300 4725 4950 4950 5175
+2 1 0 2 0 7 100 0 -1 0.000 0 0 -1 0 0 3
+	 4950 6525 6300 6525 6075 6750
+2 1 0 2 0 7 100 0 -1 0.000 0 0 -1 0 0 3
+	 2925 4500 2925 3150 3150 3375
+2 1 0 2 0 7 100 0 -1 0.000 0 0 -1 0 0 3
+	 4725 4500 4725 3150 4950 3375
+2 1 0 2 0 7 100 0 -1 0.000 0 0 -1 0 0 2
+	 1350 6525 1350 6750
+2 1 0 2 0 7 100 0 -1 0.000 0 0 -1 0 0 2
+	 2700 6300 2700 6525
+2 1 0 2 0 7 100 0 -1 0.000 0 0 -1 0 0 2
+	 3150 6525 3150 6750
+2 1 0 2 0 7 100 0 -1 0.000 0 0 -1 0 0 2
+	 4500 6300 4500 6525
+2 1 0 2 0 7 100 0 -1 0.000 0 0 -1 0 0 2
+	 4950 6525 4950 6750
+2 1 0 2 0 7 100 0 -1 0.000 0 0 -1 0 0 2
+	 6300 6300 6300 6525
+4 2 4 100 0 18 18 0.0000 4 270 930 1260 6615 SS:[ef]\001
+4 1 0 100 0 18 18 0.0000 4 195 150 2925 6615 0\001
+4 1 0 100 0 18 18 0.0000 4 210 405 2925 4815 AE\001
+4 1 0 100 0 18 18 0.0000 4 195 150 4725 6615 1\001
+4 1 0 100 0 18 18 0.0000 4 210 390 4725 4815 AF\001
+4 1 0 100 0 18 18 0.0000 4 210 630 6795 6615 SS:ii\001
+4 1 4 100 0 18 18 0.0000 4 270 825 2925 3015 SS:[e]\001
+4 1 4 100 0 18 18 0.0000 4 270 765 4680 3015 SS:[f]\001

ADDED   mttroot/mtt/lib/comp/compound/Bicausal/B2U/B2U_lbl.txt
Index: mttroot/mtt/lib/comp/compound/Bicausal/B2U/B2U_lbl.txt
==================================================================
--- /dev/null
+++ mttroot/mtt/lib/comp/compound/Bicausal/B2U/B2U_lbl.txt
@@ -0,0 +1,48 @@
+#SUMMARY B2U: undoes a bicausal bond
+#DESCRIPTION Takes e and f from bicausal bond at port [ef] 
+#DESCRIPTION and gives corresponding unicausal bonds at ports [e] and [f]
+
+## System B2U, representation lbl, language txt
+## File B2U_lbl.txt
+## Generated by MTT on Thu Jul  8 09:59:03 BST 2004
+
+  ###################################### 
+  ##### Model Transformation Tools #####
+  ######################################
+  
+  ###############################################################
+  ## Version control history
+  ###############################################################
+  ## $Id$
+  ## $Log$
+  ## Revision 1.2  2001/07/03 22:59:10  gawthrop
+  ## Fixed problems with argument passing for CRs
+  ##
+  ###############################################################
+
+## Port aliases
+#ALIAS	e	e
+#ALIAS	ef	ef
+#ALIAS	f	f
+
+## Argument aliases
+
+## Each line should be of one of the following forms:
+##	     a comment (ie starting with #)
+##	     component-name	cr_name	arg1,arg2,..argn
+##	     blank
+
+## ---- Component labels ----
+
+## Component type AE (anonymous => default parameters)
+	# AE							
+
+## Component type AF (anonymous => default parameters)
+	# AF							
+
+## Component type SS
+	[e]	SS		external,0
+	[f]	SS		0,external		
+	ii	SS		internal,internal		
+	[ef]	SS		external,0
+