I remixed the original riser to allow the purge wiper to be installed further over using the other hole in the wiper mounting arm. I also added a piece of split-open PTFE Bowden Tubing.
Newer v2 version has reduced clearances which results in less wiper movement/slop after installation. This v2 version is what is working best for me. Now my A1 Mini purges perfectly every single time!