I think there are two steps to morality engineering, either of which can fail:

1. Develop an ethical code through deliberate reflection, that is better than existing values.
2. Bind that code into the active moral code.

You say neither has happened; I disagree on both, but I'll limit this post to the second question on "binding." I use the following definitions - they may not be correct or universal, but they should be internally consistent:

• Value System: A collection of memes to do with decision-making, which provide better overall utility than innate responses.
• Moral Code: An individual's value system that drives day-to-day decision making through emotional response.
• Ethical Code: A value system derived from deliberate study ("Ethics").

Evolution of Morality

Let's take as a given that emotions drive behavior, and an emotion-driven response will always trump an analytic response. Let's take evolutionary psychology and memetics as a given, and posit that human evolution is largely memetic at this point, with genetic evolution driven largely by ability to host memes.

We'll go one step further and say that a key trait of modern humanity is the ability to give a meme access to our emotional centers. This is the basis of morality - a learned rule triggers an emotional response to counter or modify our innate "animal" emotional response, modifying behavior. Most likely brains that allow acquired memes to trigger strong emotions co-evolved with memes that help us survive in tribes. This is an "evolution-of-evolution" event. instead of a lever on

phenotypes like modularity or a lever on recombination like sex, we evolved a lever on learned thought patterns by allowing them to tap directly into our emotional core.

We survive now based on the quality of our meme sets, and the best surviving memes tend to include a trigger and strong emotional response. This unlocks an evolutionary path tens of thousands of times faster than genetics, and allows horizontal transfer within a generation. Within this framework, morality memes evolve individually (Fire is comforting, not scary), then in colonies (also, this is how to make new fire and keep old fire burning), and finally into "memetic organisms" - proto-religions and proto-cultures. These are messy and include memes that only make sense in the context of others, but their defining feature is that they tie in to the emotional core.

Leaning on some en vogue evolutionary theories, a meme that is fashionable can become hard-wired. If you need to do it anyway, and it's related to sexual selection, hard-wiring it may free up mental resources for more complicated memes. At the extreme, entirely new emotions may be developed (e.g. shame or embarassment).

Ethical Transplants

Engineering an ethical code - whether its for Attorneys or Humanists - doesn't guarantee that anyone will follow it. Following the code in the face of innate or moral emotion requires an emotional hook. There are two major emotional pathways an ethical code can follow, and they're both indirect. There can be an external enforcer - God, the Police, the Bar Association, or Santa Clause - which followers fear. There can be an internal hook within the moral code which says "it is moral to follow applicable ethical codes." Both approaches are weak and indirect compared to an innate emotional reaction.

Religion

Binding an ethical rule to an emotional response results in a moral tenet that will actually be followed. We can call the beliefs, rites, and rituals that bind and activate the tenet religion, we can call the strength of that binding morality (these aren't the precise meanings of those words, but they are familiar and relevant). Religions are selected for their morality and the extent to which they promote survivability (in some ethical systems that's the same as being ethical, YMMV). They include not only the values-memes themselves, but the layers of memes that bind them.

Conclusion

Ethically-derived values don't work without emotions, because we act on emotions and rationalize after. Repeated and emotional rituals (religions) instantiate morality by binding ethical tenets to emotional responses. Once you know this, you can engineer a religion just like any other virus:

1. Lay out your ethically-derived values.
2. Add values for maintaining your religion/beliefs and passing to others.
3. Collect existing rites, rituals, stories, and beliefs that bind value to emotions, and develop new ones if needed.
4. Compress and self-reference as much as possible to reduce package size.

Like any other bio-engineering, you lose some control once you release it, and your engineered religion is going into combat with all others.