I had a weird issue where my character suddenly disappeared from the screen, and it became impossible to continue. It was still possible to interact with the NPCs through dialogue, but moving your character so the screen would pan and reveal the exits (hoping that by entering another area, my character would "reset") no longer worked. The character was effectively off the screen somehow, and could no longer move around.
So I opened my savegame in the hopes that like so many other files for this game, it would be something human readable. Indeed, it's just a bunch of XML. I will document what I did in order to fix my issue, in case someone else stumbles into this bug.
First things first, you need to figure out which of many tags contains info on your character. If you're playing with Nate, I believe you need to scan for characters_mensch. If you're the critter, scan for characters_vieh. You want to find the tag that contains attributes for offset and rotation. In my case, it looked like this:
<characters_vieh offset="-nan -nan -nan" rotation="-nan -nan -nan -nan" parent="_game" scene="scenes_eisplatte" scale="0.999988" customOP="" exDist="280">
Somehow, the game messed up the position and replaced all numbers with "nan" (not a number). Easy enough fix; just change the position to "0 0 0" and rotation to "1 0 0 0" and you're in business:
<characters_vieh offset="0 0 0" rotation="1 0 0 0" parent="_game" scene="scenes_eisplatte" scale="0.999988" customOP="" exDist="280">
Hope this may help someone with a similar issue in the future.