Message from 'git-rebase'; German translation

As I know how hard translations can be, esp. with that much technical terms inside, I'm usually expecting _not_ to yield the same result when translating a software's translation back to English.

However, git-rebase just threw these two sentences at me (And though i know their meaning, i couldn't get the meaning from the message, it gave). Both are in context of starting a rebase while one is already in progress.

first is:

Original: ... and I wonder if you are in the middle of another rebase.

German git translation: ... und es wäre verwunderlich, wenn ein Neuaufbau bereits im Gange ist.

And a re-translation back to English from my understanding as native German speaker: ... and it would be astonishing (=i'd be surprised), if a rebase was already in progress.

And second:

Original: I am stopping in case you still have something valuable there.

German git translation: Es wird angehalten, falls bereits etwas Nützliches vorhanden ist.

I wanted to point out that "etwas Nützliches" is more "something useful" that "something valuable". But the more I thought about it, the more it started to confuse me (even the original text) - and now I feel like I don't understand the meaning of the last sentence at all; neither in English nor in the German translation: After removing the directory with all rebase-information inside it, WHERE should something valuable still be left over? Is it referring to my working tree?

So, for completeness, the full English message:

	It seems that there is already a rebase-merge directory, and
	I wonder if you are in the middle of another rebase.  If that is the
	case, please try
     	   git rebase (--continue | --abort | --skip)
	If that is not the case, please
	        rm -fr "/work/lg2/src/.git/rebase-merge"
	and run me again.  I am stopping in case you still have something
	valuable there.

Sascha