I'm trying to repeat a diagram using PlantUML. The diagram is like this:
I got stuck at trying to add more connections and make them look decent.
I started with object digram and came to something like this link to online diagram.
As soon as I start adding more connections, blocks break into chaos.
Then I tried component diagram. I started from this diagram and got to something like this in trying to add one more blocks and connections: link to online diagram.
The result is not satisfactory. I would appreciate any help in trying to add one more block to the diagram.

I always try to keep it simple, using
-->(vertical) layout as much as possible. That is the optimal strategy for the GraphViz algorithm, which is the basis of PlantUML.The result is different from your original, but I hope you find it readable: