"super-lube" seems to be the one people like the most. I would check since you are in Germany with Zapp or the Limey what they have found in the EU that works best since I am not sure if the super-lube brand is available out there.

As far as the spring, I would not remove or cut it. Probably best to shoot Franco a PM on here or email the folks at Bishop. It may be something really simple to remedy.