diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -58,4 +58,8 @@
 
 ## 0.6.4.0 -- 2024-03-08
 
-* Adding leg getter in CartesianClosedCategory
+* Adding leg getter in CartesianClosedCategory
+
+## 0.6.5.0 -- 2024-05-16
+
+* Changes to simplification of CGMorphism
diff --git a/FiniteCategories.cabal b/FiniteCategories.cabal
--- a/FiniteCategories.cabal
+++ b/FiniteCategories.cabal
@@ -14,7 +14,7 @@
 -- PVP summary:      +-+------- breaking API changes
 --                   | | +----- non-breaking API additions
 --                   | | | +--- code changes with no API change
-version:             0.6.4.0
+version:             0.6.5.0
 
 -- A short (one-line) description of the package.
 synopsis: Finite categories and usual categorical constructions on them.
diff --git a/src/Math/Categories/FinSketch.hs b/src/Math/Categories/FinSketch.hs
--- a/src/Math/Categories/FinSketch.hs
+++ b/src/Math/Categories/FinSketch.hs
@@ -27,6 +27,7 @@
     ConeSketch(..),
     CoconeSketch(..),
     TripodSketch(..),
+    FunctorSketch(..),
     SketchError(..),
     constructTwoConeFromTripod,
     constructTwoConeFromTripodText,
diff --git a/src/Math/Categories/FunctorCategory.hs b/src/Math/Categories/FunctorCategory.hs
--- a/src/Math/Categories/FunctorCategory.hs
+++ b/src/Math/Categories/FunctorCategory.hs
@@ -197,7 +197,7 @@
                       Diagram c1 m1 o1 c2 m2 o2 -> Maybe (DiagramError c1 m1 o1 c2 m2 o2)
     checkFiniteDiagram d@Diagram{src=s,tgt=t,omap=om,mmap=fm}
         | domain om /= ob s = Just WrongDomainObjects{srcObjs = ob s, domainObjs = domain om}
-        | not $ (genArrows s) `isIncludedIn` (domain fm) = Just WrongDomainMorphisms{srcMorphs = arrows s, domainMorphs = domain fm}
+        | not $ (genArrows s) `isIncludedIn` (domain fm) = Just WrongDomainMorphisms{srcMorphs = genArrows s, domainMorphs = domain fm}
         | not $ image om `isIncludedIn` ob t = Just WrongImageObjects{imageObjs = image om, codomainObjs = ob t}
         | not $ image fm `isIncludedIn` arrows t = Just WrongImageMorphisms{imageMorphs = image fm, codomainMorphs = arrows t}
         | not.(Set.null) $ tear = Just TornMorphism{f = anElement tear, fImage = d ->£ (anElement tear)}
diff --git a/src/Math/FiniteCategories/CompositionGraph.hs b/src/Math/FiniteCategories/CompositionGraph.hs
--- a/src/Math/FiniteCategories/CompositionGraph.hs
+++ b/src/Math/FiniteCategories/CompositionGraph.hs
@@ -148,7 +148,6 @@
     -- | Helper function for `simplify`. Returns a simplified raw path.
     simplifyOnce :: (Eq a, Eq b) => CompositionLaw a b -> RawPath a b -> RawPath a b
     simplifyOnce _ [] = [] 
-    simplifyOnce _ [e] = [e]
     simplifyOnce cl list 
         | new_list == [] = []
         | new_list /= list = new_list