To install iobroker http://iobroker.net/ just execute:

pkg install npm
curl -sLf https://iobroker.net/install.sh | bash -

I had the problem, that on some ports iobroker wants to use an already occupied port, so I did:

cd /opt/iobroker
iobroker setup custom

and changed it to

Current configuration:
- Objects database:
  - Type: file
  - Host/Unix Socket: 127.0.0.1
  - Port: 9101
- States database:
  - Type: file
  - Host/Unix Socket: 127.0.0.1
  - Port: 9100
- Data Directory: ../../iobroker-data/

After this start iobroker with:

service iobroker restart

Install KNX 1.0.39, connect to localhost:3671 using pyhs. EIB adress 0.0.0. Import your KNX project and then downgrade knx to 1.0.20. Restart iobroker.

After this you should be able to write to your KNX by changing the state of an object.

Use sql to store history. I use as backend a postgresql database.

Create the user with:

su postgres
createuser -sdrP iobroker