Now as you say I should try increasing temprature and extrusion flow. I could use a hint here how much to increase the multiplier.
By using a spcified startpoint I probably get as close to the most cooled down area for the next layer.
You can increase the flow of filament through the extrusion multiplier setting on "Primary Extruder Toolhead" page. Click "Edit Process Settings" from the first page, then click "Show Advanced" to see the "Extrusion Multiplier" setting. Adjust to 1.1 or 1.2 to increase the flow 10 or 20 percent respectively.
Before you adjust the flow, increase the extrusion temps.... found under the "Temperature" tab, in the "Primary Extruder" section. From the "Cooling" tab, you can adjust the layer and amount of fan flow... I like to use 20-30% as max fan for ABS.
Hope that helps... and yes its a painful trial and error process to tune the setting to your printer.