Really looking forward to your progress report. This is one major undertaking.
You might want to take a look at the German language forums. They have people who already done this model or have it under construction. It could help avoid some pitfalls. Although based on your previous reports I'm pretty sure you are fully capable of dealing with any issue...
Can't help with the swastika. Personally I would build as it is. Otherwise modifying original art-work in graphic software would be my first choice.
Olo, not sure if this is of any help but this
guy in Florida is a good source for display cases. Good luck.
Darius