haha, okay you've made a slight error.
The KKL adaptors are only for KKL cables. As you have an ELM cable, you don't need to use any of the KKL adapters.
Just plug your ELM cable straight into your laptop and directly into the OBD port (no adapter cables required) and the ELM cable will be able to deal with it.
MultiECUScan has the ability to scan for present ECUs, so once connected and you've set your COM port just use the software to search for connected ECUs, one of them will be the.
Think the ECU is something like BOSCH EDC16CF4 on these motors, off the top of my head or something similar to that.
As for what the fault is - who knows mate. The excess coolant is a new one on me, not heard that before. Have you kept up with the cambelt services and did you have the waterpump done at the same time?
1999 156 1.8TS Sport Pack 3
2001 166 3.0 V6 24V Super
2003 156 GTA 3.2 V6 24V
2005 156 1.9 JTDM-Jet Sport
2008 159 1.9 JTDM Lusso
1997 GTV 2.0TS Lusso
2001 147 1.6TS Lusso