At least we can immediately see what was wrong with your original installation:
warn [28 May 19 10:09:13 +02:00] You are using Node.js 12.3.1 which is not yet supported by Adapt. If you encounter issues, please downgrade to 8 || 10.
The latest authoring tool code supports both Node 10 & 12 so starting again from scratch should solve your problems.