Kaimana,
I agree with the advice already given - don't attach the photoetch rails to wood, because wood is not stable and will flex with changes in temperature and humidity, popping your rails loose.
I would add that if there is no edge lip of plastic, or if you make changes that remove the molded edge, you can add new lip with sheet plastic. 

I did this with my Revell Olympia build; having sanded away the kit deck edge lip, I replaced it with Evergreen plastic strips and later added the rails on top of the new lip.
 
  Best of luck with your Prinz Eugen! 
