I thought I'd try it again to make sure:

I boot knoppix, typing "knoppix64 noimage" to boot without using the overlay partition. It's just as if I booted knoppix with the live dvd.

Then I mount the reiserfs overlay partition on /dev/sdb2 readonly on /mnt/a just so I can access my mamepackages which I've previously downloaded.

Once I install the 0.186 dmo packages with dpkg, the mame lua console and the plugins work. If you go to the plugins menu in mame, the menu shows all the normal plugins.


Code:
knoppix@Microknoppix:~$ mame
bash: mame: command not found
knoppix@Microknoppix:~$ sudo mkdir /mnt/a; sudo mount /dev/sdb2 /mnt/a -o ro
knoppix@Microknoppix:~$ ls /mnt/a/home/knoppix/mamepackages/
mame_0.182-1_i386.deb         mame-data_0.182-1_all.deb
mame_0.186-dmo1_amd64.deb     mame-data_0.186-dmo1_all.deb
mame_0.186-dmo1_i386.deb      mame-data_0.189+dfsg.1-1_all.deb
mame_0.189+dfsg.1-1_i386.deb  mame-extra_0.182-1_all.deb
mame_0.192-dmo1_i386.deb
knoppix@Microknoppix:~$ time sudo dpkg -i /mnt/a/home/knoppix/mamepackages/mame_0.186-dmo1_i386.deb /mnt/a/home/knoppix/mamepackages/mame-data_0.186-dmo1_all.deb 
Selecting previously unselected package mame.
(Reading database ... 449729 files and directories currently installed.)
Preparing to unpack .../mame_0.186-dmo1_i386.deb ...
Unpacking mame (1:0.186-dmo1) ...
Selecting previously unselected package mame-data.
Preparing to unpack .../mame-data_0.186-dmo1_all.deb ...
Unpacking mame-data (1:0.186-dmo1) ...
Setting up mame-data (1:0.186-dmo1) ...
Setting up mame (1:0.186-dmo1) ...
Processing triggers for man-db (2.7.6.1-2) ...
Processing triggers for menu (2.1.47+b1) ...

real    0m15.095s
user    0m6.235s
sys    0m5.348s
knoppix@Microknoppix:~$ mame -console
    _/      _/    _/_/    _/      _/  _/_/_/_/
   _/_/  _/_/  _/    _/  _/_/  _/_/  _/       
  _/  _/  _/  _/_/_/_/  _/  _/  _/  _/_/_/    
 _/      _/  _/    _/  _/      _/  _/         
_/      _/  _/    _/  _/      _/  _/_/_/_/    

mame 0.186    
Copyright (C) Nicola Salmoria and the MAME team

Lua 5.3    
Copyright (C) Lua.org, PUC-Rio

[MAME]> 
knoppix@Microknoppix:~$ mame -verbose -console
    _/      _/    _/_/    _/      _/  _/_/_/_/
   _/_/  _/_/  _/    _/  _/_/  _/_/  _/       
  _/  _/  _/  _/_/_/_/  _/  _/  _/  _/_/_/    
 _/      _/  _/    _/  _/      _/  _/         
_/      _/  _/    _/  _/      _/  _/_/_/_/    

mame 0.186    
Copyright (C) Nicola Salmoria and the MAME team

Lua 5.3    
Copyright (C) Lua.org, PUC-Rio

Available videodrivers: x11 wayland dummy 
Current Videodriver: x11
    Display #0
        Renderdrivers:
                opengl (0x0)
             opengles2 (0x0)
              software (0x0)
Available audio drivers: 
    pulseaudio          
    alsa                
    sndio               
    dsp                 
    disk                
    dummy               
Build version:      0.186 (unknown)
Build architecure:  
Build defines 1:    SDLMAME_UNIX=1 SDLMAME_X11=1 SDLMAME_LINUX=1 
Build defines 1:    LSB_FIRST=1 
SDL/OpenGL defines: SDL_COMPILEDVERSION=2005 USE_OPENGL=1 
Compiler defines A: __GNUC__=4 __GNUC_MINOR__=2 __GNUC_PATCHLEVEL__=1 __VERSION__="4.2.1 Compatible Clang 3.8.1 (tags/RELEASE_381/final)" 
Compiler defines B: __unix__=1 __i386__=1 
Compiler defines C: __USE_FORTIFY_LEVEL=0 
...

and the version of Knoppix:

knoppix@Microknoppix:~$ cat /mnt-system/KNOPPIX/kversion 
8.1-2017-09-05


knoppix@Microknoppix:~$ uname -a
Linux Microknoppix 4.12.7-64 #13 SMP PREEMPT Tue Aug 15 04:56:38 CEST 2017 x86_64 GNU/Linux


knoppix@Microknoppix:~$ lsb_release -a
No LSB modules are available.
Distributor ID:    Debian
Description:    Debian GNU/Linux 9.1 (stretch)
Release:    9.1
Codename:    stretch