i found this codes for the Munster Pinball, some are double finds posted by other users
I will post them in this way, like it was descripted in the Code update readme file:
- Added Team Credits ESaster egg: 1 2 3. To see it you Hold in Both flippers,
then you enter numbers with the left flipper and enter on with the right.
Finally, when you are done you have to enter one last time with the right
flipper. So 1 2 3 would be B LR LLR LLLR R

1 2 3 = Credits
4 5 1 = Dead Flip
3 3 3 = Hello World
3 6 5 = Chris Franchi
4 4 6 = Pinball Team
7 1 4 = XAQ i missed you
8 4 7 = Serial Number?

i am searching any information about the secret mania mode, this way i stumbled upon the codes.

Yes the last reply i think explains it quite good:
B=Both Flippers
L=Left Flipper
R=Righ Flipper.
Sequence starts always with one time Both Flippers.
Then the Number how often to press the Left flipper, 2 would be press two times Left Flipper.
The 1. Sequence of Lefts will be ended with a Right Flipper.
Then the 2nd Sequence of Lefts start, ended again with a right flipper.
3rd sequence with lefts, ended this time with 2 right flippers.

1 2 3 = B LR LLR LLLRR = Credits
4 5 1 = B LLLLR LLLLLR LRR = Dead Flip
3 3 3 = B LLLR LLLR LLLRR = Hello World
3 6 5 = B LLLR LLLLLLR LLLLLRR = Chris Franchi
4 4 6 = B LLLLR LLLLR LLLLLLRR = Pinball Team
7 1 4 = B LLLLLLLR LR LLLLRR = XAQ i missed you
8 4 7 = B LLLLLLLLR LLLLR LLLLLLLRR = Serial Number?

I hope this helps have fun with the codes.
and sorry i am not good in explaining, but if you know the procedure it should be quite easy.

would be a coincidence. ERW would translate to 5 18 23 so the sequence would be:
B 5xL R 18XL R 23xL RR
in words, Both Flippers, 5 Times left flipper, 1 time right Flipper, 18 Times Left Flipper, 1 Time Right Flipper, 23 Times Left Flipper, 2 Times right flipper.

You can try yourself
When i play the next time i will try too

maybe it's the secret code for secret mania, who knows

ERW does nothing on the munster

Hello Chuck, i think i have to correct me.
I am not sure how it works, i used pinball browser to see a little in the code, there is section for you:

HIYA CHUCK
THANK YOU FOR YOUR HELP

When the SD-Card Code is opened in Pinball Browser there is a section for messages, there this text can be seen.

there seems to be an easter egg, but i am not sure how it is started, maybe when the initials are put in. I tried your initals as flipper code, but it did not work.

Had you an ester egg with erw on an other machine? do you know how it did work there?

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