Take a look at the Adobe Professional Certification: Adobe Captivate. https://www.adobe.com/products/captivate/certificate.html

It includes online video tutorials, exercise files that you can work through, and virtual instructor-led training. I am one of the facilitators of the virtual instructor-led training. While learning to use Adobe Captivate cannot be satisfied with a single program, this program is a great start. Once you have completed such a program, there are many online resources to continue your learning, and you should practise your skills right away, rather than allowing them to end up in cold storage.

You will not find a ‘learning path’ in my answer.  My deep conviction is that such a clear path doesn’t exist at all. After many decades of training and teaching for all kinds of topics (from Flute teaching over Project Management for building sites to lot of Software training) to all types of trainees/students (kids, adults, workplace learning, immigrants with different background, unemployed seniors looking for a new career) my conclusion is that a learning path can only be efficient if it is built on the existing skills and talents of the trainees.

More specifically about your very broad question ‘elearning multimedia developer’. No one is a dummy concerning ‘learning’ because everyone had a learning career. Same for multimedia. Do you have pedagogical skills, are you creative (not limited to graphics, but in all ways)? What is your history with IT?

More specified, since you mention Captivate. I have been using Captivate since over 15 years, and very intensively since 12 years (have a look at my activity in this community, on the Adobe forums, and in my personal blog).  As a former researcher I have used that skill to find lot of unknown workflows and tweaking solutions, but still am learning.

What is your preferred way of learning? Only video – perfect for small step-by-step procedures? Particpating in webinars? Reading articles providing more insight besides step-by-step workflows? Is your goal to create all types of eLearning or do you want to focus on a specific type? Are you using other Adobe applications (or alternatives), which are necessary to create the multimedia assets, or will you use only Stock images? Example: using Photoshop for bitmap images (editing or creation) or short video editing, using Illustrator for vector images, Audition to improve audio quality of voice overs, Animate to create HTML animations.

You can easily find videos and blogs everywhere for workflows.  I want to offer you only one link to a blog, where I explain which topics seem to be challenging for most Captivate users (new and intermediate). This article is based on my experiences answering question daily about Captivate and on my career as Captivate trainer and consultant.

http://blog.lilybiri.com/challenges-for-starters