Pass system in Houdini is different to xsi, but very powerfull, too. Where xsi is very streamlined with a certain workflow, in houdini it is up to You how to setup passes with the toolset.
mantraRops are like passes, You can specify if or how mantra renders certain things in the object tab. i use it for example to prevent nodes to appear in my renders, that are just for processing. You can easily do this by establishing a naming convention in You scene. for example by naming all renderable objects with a ren_ prefix and adding the wildcard ren_* in the candidate object field no other object gets rendered. wildcards are very powerful in houdini.
another way is to use bundles, in houdini they are the closest thing to groups/partitions in xsi. bundles can be used in many places, where a list of object is needed, for example shadow mask.
Another great tool set are takes. takes store parameter overrides per take and as soon as You switch to that take all overrides are applied, all output nodes, like mantraROP, have a take field where You can specify the take it should be processed with. Takes are not limited to rendering, You can use it for lowres/highres sim setups, for simulations with different seeds, for animation takes, all stored in one setup.
Another thing about takes to mention is that they can be stacked, for example You create a RENDER take and set all objects to be hidden. now add child takes to this and setup You different passes, with that child takes. Unhide objects, change materials, change what You need in that particular child take used for that pass. when working in maintake, where most of Your setup work will happen You can not really break any of Your renders, as long as You as You hide new objects in that RENDERTAKE. You can script that, too.
When the child take of RENDER is active, all overrides set by RENDER are applied, and are only overwritten by the child take. The described workflow is just a example to explain the hierarchy nature of takes.
it might be a little bit confusing at the beginning, but it is very powerful. And as far as I remember when I hit the world of passes in xsi the first time in version 2 it was confusing in the beginning, too.
hope that helps You to get started with that subject.
for that keyboard thing, I must admit I use US or UK keyboards since 10 years, because their layout works just fine with the applications I use. and i do not really care that I have no ä, ö or ü