I came from JDE world back ground and has over 12 years experience as developer.
Now I work as JDE E1 BA but would love to learn E1 development methods.
Please let me know the best approach for this.
Just get your head around the granular event based sides of things.
RPG is a script, E1 screens and UBEs don't work that way as such, they are event driven.
Once you get your head around what each one does, it's fairly easy. Especially if you've been programming in RPG
Years ago (I was similar to you RPG background) I developed a table, screen and UBE to gkeep a track of which of my mates had borrowed what DVD
A table to enter the film names etc, a screen to enter the names, a UBE to run and remind me each week who had what.
I'd get demo Jnr installed somewhere and knock yourself out
Despite the proof, I never got half of my DVDs back by the way