Can't build error - dll is not allowed to be included or could not be found.

I'm trying to build and run my project but I keep getting errors. I believe the errors are related to the script I'm using called Uniducial, w$$anonymous$$ch references a program called reacTIVision to track markers with a camera. The error I'm getting is somet$$anonymous$$ng to do with Unity Editor and DLLs. I'm way out of my depth here. Help!? T$$anonymous$$s is the error:

ArgumentException: The Assembly UnityEditor is referenced by UniducialLibrary. But the dll is not allowed to be included or could not be found. UnityEditor.AssemblyHelper.AddReferencedAssembliesRecurse (System.String assemblyPath, System.Collections.Generic.List1 alreadyFoundAssemblies, System.String[] allAssemblyPaths, System.String[] foldersToSearch, System.Collections.Generic.Dictionary2 cache) (at C:/BuildAgent/work/6bc5f79e0a4296d6/Editor/Mono/AssemblyHelper.cs:52) UnityEditor.AssemblyHelper.AddReferencedAssembliesRecurse (System.String assemblyPath, System.Collections.Generic.List1 alreadyFoundAssemblies, System.String[] allAssemblyPaths, System.String[] foldersToSearch, System.Collections.Generic.Dictionary2 cache) (at C:/BuildAgent/work/6bc5f79e0a4296d6/Editor/Mono/AssemblyHelper.cs:55) UnityEditor.AssemblyHelper.FindAssembliesReferencedBy (System.String[] paths, System.String[] foldersToSearch) (at C:/BuildAgent/work/6bc5f79e0a4296d6/Editor/Mono/AssemblyHelper.cs:86) UnityEditor.HostView:OnGUI()

I also get these errors, but I t$$anonymous$$nk they're related to the above one:

Error building Player: Extracting referenced dlls failed. UnityEditor.HostView:OnGUI()

And:

Exception: Error building Player: Extracting referenced dlls failed. UnityEditor.BuildPlayerWindow.BuildPlayerWithDefaultSettings (Boolean askForBuildLocation, BuildOptions forceOptions) (at C:/BuildAgent/work/6bc5f79e0a4296d6/Editor/Mono/BuildPlayerWindow.cs:341) UnityEditor.BuildPlayerWindow.GUIBuildButtons (Boolean enableBuildButton, Boolean enableBuildAndRunButton, Boolean canInstallInBuildFolder) (at C:/BuildAgent/work/6bc5f79e0a4296d6/Editor/Mono/BuildPlayerWindow.cs:942) UnityEditor.BuildPlayerWindow.ShowBuildTargetSettings () (at C:/BuildAgent/work/6bc5f79e0a4296d6/Editor/Mono/BuildPlayerWindow.cs:923) UnityEditor.BuildPlayerWindow.OnGUI () (at C:/BuildAgent/work/6bc5f79e0a4296d6/Editor/Mono/BuildPlayerWindow.cs:697) System.Reflection.MonoMethod.Invoke (System.Object obj, BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) Rethrow as TargetInvocationException: Exception has been thrown by the target of an invocation. System.Reflection.MonoMethod.Invoke (System.Object obj, BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) System.Reflection.MethodBase.Invoke (System.Object obj, System.Object[] parameters) UnityEditor.HostView.Invoke (System.String methodName, System.Object obj) (at C:/BuildAgent/work/6bc5f79e0a4296d6/Editor/Mono/GUI/DockArea.cs:213) UnityEditor.HostView.Invoke (System.String methodName) (at C:/BuildAgent/work/6bc5f79e0a4296d6/Editor/Mono/GUI/DockArea.cs:206) UnityEditor.HostView.OnGUI () (at C:/BuildAgent/work/6bc5f79e0a4296d6/Editor/Mono/GUI/DockArea.cs:107)