BMW Motorcycle stuck ignition/starter/kill switch - and how to fix it

I noticed that my starter switch was stuck on my BMW F700GS wouldn't work, and was stuck or sticking, and that a lot of people had the same problem on all types of BMWs, including the S1000R, the F800GS and pretty much any bike with this starter switch (which is quite a few of them).
This fix will work for all BMW motorcycles which use the same starter switch assembly (which has to be probably the worst ever). I hope this helps, please let me know if you have any questions.
You will need a Torx T9 screwdriver (a thin one at that) - but the BMW schematic says a Torx T15 - which is very very wrong.
Please let me know if this worked for your model BMW and I will include it in this description