"Undoing" this patch is enough to restore the coverage of combining chars 
which was present before math symbols started to get in the way: one should:
  
A) remove math greenkeys from kbdd file, 
B) disable uni_manual (except for phonetization, where only ? --> ? gets in the way),
C) turn off recognition of SQUARED/OPERATOR/SIGN/IN TRIANGLE.

--- examples/EurKey++.kbdd	2012-02-19 23:14:32.372000000 -0800
+++ examples/EurKey++.kbdd-ook	2012-02-19 21:52:37.637200000 -0800
@@ -95,7 +95,7 @@ ExportDeadKeys=	´  ˋ  ˜  ˆ  ˇ  °
 @char2key_prefer_first=\,|,.,002c
 #
 # Will be only considered when putting a diacritic on AltGr-key (~∼, *∗, .⋅ )
-@AltGrCharSubstitutions=ijü
+@AltGrCharSubstitutions=ijü,^∧,&∩,*×,#≠,6∨,7∪,|∣
 #
 # Tibetan range: take only tibetan diacritics, so our code adding diacritics won't be confused by prefices... ???
 Auto_Diacritic_Start=0f00
--- lib/UI/KeyboardLayout.pm	2012-02-19 23:32:19.630400000 -0800
+++ lib/UI/KeyboardLayout.pm-ook	2012-02-19 22:33:04.515200000 -0800
@@ -3964,8 +3964,7 @@ my %operators = (DOT => ['MIDDLE DOT', '
 		 'DOUBLE SOLIDUS' => ['PARALLEL TO'], MINUS => ['HYPHEN-MINUS']);
 
 #			THIS IS NOT A MULTIMAP!
-my %uni_manual = (phonetized => {qw( 0 ə  s ʃ  z ʒ  j ɟ  v ⱱ  n ŋ  V ɤ  ! ǃ  q ʔ  ¿ ʕ )},
-); my %ignore = (
+my %uni_manual = (phonetized => {qw( 0 ə  s ʃ  z ʒ  j ɟ  v ⱱ  n ŋ  V ɤ  ! ǃ  ? ʔ  ¿ ʕ )},
 		  addline    => {qw( 0 ∅  ( ∈  ) ∋  = ≡  ≡ ≣  † ‡  + ∦  / ∠  | ∟  . ∸  ∨ ⊻  ∧ ⊼ )},	# conflict with modifiers: qw( | ‖  _ ‗ )
 		  addtilde   => {qw( 0 ∝  / ∡  \ ∢  ∫ ∱  : ∻  - ≂  ≠ ≆  ~ ≈  ∼ ≈  ≃ ≊  ≈ ≋  = ≌  ( ⟅  ) ⟆ )},	# not on 2A**
 		  addleft    => {qw( = ≔  × ⨴  × ⋉  \ ⋋  + ⨭  → ⧴)},	#  × ⨴ is hidden
@@ -4013,7 +4012,7 @@ sub parse_NameList ($$) {
         if ($name =~ /^(.*)\s+(?=OR\s)(.*?)\s*$/) {	# Find the latest possible...
           push @{$candidates{$k}}, [$1, $2];
         }
-        if (($t = $name) =~ s/\b(COMBINING(?=\s+CYRILLIC\s+LETTER)|BARRED|SLANTED|APPROXIMATELY|ASYMPTOTICALLY|ALMOST|^xxx-SQUARED|LUNATE|SIDEWAYS(?:\s+(?:DIAERESIZED|OPEN))?|INVERTED|ARCHAIC|SCRIPT|LONG|TURNED(?:\s+(?:INSULAR|SANS-SERIF))?|REVERSED|OPEN|CLOSED|DOTLESS|FINAL)\s+|\s+(BAR|SYMBOL|xxx-OPERATOR|xxx-SIGN|xxx-IN\s+TRIANGLE)$//) {
+        if (($t = $name) =~ s/\b(COMBINING(?=\s+CYRILLIC\s+LETTER)|BARRED|SLANTED|APPROXIMATELY|ASYMPTOTICALLY|ALMOST|^SQUARED|LUNATE|SIDEWAYS(?:\s+(?:DIAERESIZED|OPEN))?|INVERTED|ARCHAIC|SCRIPT|LONG|TURNED(?:\s+(?:INSULAR|SANS-SERIF))?|REVERSED|OPEN|CLOSED|DOTLESS|FINAL)\s+|\s+(BAR|SYMBOL|OPERATOR|SIGN|IN\s+TRIANGLE)$//) {
           push @{$candidates{$k}}, [$t, "calculated-$+"];
           $candidates{$k}[-1][1] .= '-epigraphic'   if $t =~ /\bEPIGRAPHIC\b/;	# will be massaged away from $t later
           $candidates{$k}[-1][0] =~ s/\s+SYMBOL$// and $candidates{$k}[-1][1] .= '-symbol' 
@@ -4081,7 +4080,7 @@ sub parse_NameList ($$) {
       my $name = $NM{$self->charhex2key($base)};
       next if not $name and ($k =~ /^[12]?F[89A]..$/ or hex $base >= 0x4E00 and hex $base <= 0x9FCC);		# ideographs; there is also 3400 region...
       warn "Basic: `$k' --> `@$exp', base=`$base' --> `",$self->charhex2key($base),"'" unless $name;
-      if ((my $NN = $name) =~ s/\s+xxx-OPERATOR$//) {
+      if ((my $NN = $name) =~ s/\s+OPERATOR$//) {
 #warn "operator: `$k' --> <$NN>, `@$exp', base=`$base' --> `",$self->charhex2key($base),"'";
         push @{$candidates{$k}}, [$_, @$exp[2..$#$exp]] for $NN, @{ $operators{$NN} || []};
       }