i think part of the confusion is that mame-libretro is a rom folder installed in ~/RetroPie/ where you put your roms in for any of the libretro MAME cores. eg, this folder is used for the default lr-mame2003 core that uses the 0.78 MAME romset. however, there is also a 'lr-mame' ("libretro-mame") emulator that is an experimental (not installed by default), that uses the current (or close to) MAME romset.

in any case, put your 0.78 roms in /mame-libretro/, use lr-mame2003, and if you get any issues please post the verbose log as instructed.

I don't use bezels, but I just wanted to say that it's worth it to emulate the Williams clone of 1942 (lr-fba works well). Unlike the Capcom/Romstar version, the Williams version correctly refers to the 2nd button evasion maneuver as a Loop, not Roll, and consequently has Ls in the lower right corner instead of Rs. Also, the stage names are better (clearer).

The gist of the Getting Started guide for Arcade is that users need to 1) pick your arcade emulator and then 2) you find the exact romsets designed for that emulator version

Your emulator is mame2003 and it will only work with a MAME 0.78 collection. If you have a MAME 0.78 romset collection you will not get CRC errors and the games will, generally, play.

The MAME 0.78 romset collection is very easy to find on the internet. No Dark Web required, just a search engine :)