I'm a Palace fan living in Basel, Switzerland and will try to make it to the game. Looks like the stadium is to the east of the town alongside the river Lech. The local FC-Fuessen play there. The street name is Rotwandweg (red wall way so we need to make this Rotundblauwandweg!) and just below it on the map you will see the Sportanlagen (sports centre). Here's a link to a pdf map of the town: http://www.stadt-fuessen.de/fileadmin/fuessen/images/stadtplaene/Stadtplan.pdf
Hope a to see a few CP fans there!
ciao for now,
Simon