This paper discusses the challenges and obstacles encountered in developing and publishing Open Educational Resources (OER) in engineering ethics education at a higher academic level, in the project Ethics Education for Engineers of the 4TU.Centre for Ethics and Technology. The main aim is to contribute to the larger project of providing OER at university level by providing insights gained from the process of gathering and publishing materials. These insights are intended to be suitable for use by other authors and teachers of OER. First, we provide an introduction describing the parties involved and the specific aim of our project. Second, we describe the difficulties that were expected in the proposal phase of the project and explain how we anticipated solving them. Third, we discuss the different problems we encountered once the project was put into practice. We describe in what way we answered to these unexpected challenges. Fourth, an overview is given of valuable lessons learned and some practical take-aways acquired through experience. Here we also discuss the character of ethics in the context of making modules suitable for empirically trained students and mention some possible blind-spots that 4TU.Ethics might not be able to consider from its sole perspective. Finally, we summarise what we have come to understand are the most important steps in undertaking a project such as this by manner of a blueprint for people attempting something similar in the future.