[Game Box covers no longer downloading]

So after a few hours of importing games , suddenly games covers stopped getting downloaded accross several platforms ( PSPS/ switch ) 

 

The old ones still show but all new games wont download . 

 

I tried re-installing both Launchbox and replacing different roms .. Same issue 

[NeoGeo and Arcade Emulation and Nonclemanture]

I am mainly interested in Neo Geo emulation for the sake of healing my by broken childhood dreams of playing arcade games at home . I have been messing around with different front ends, devices and emulators to get this working , I just purchased premium as I hoped I could get something fancy looking on Lunchbox. I am particularly interested in getting the artwork working , though from what I see , this is the most challenging since much of the artwork is missing 

 After some research , it appears Final Burn Alpha and Final Burn Neo cores emulation is more user friendly than MAME emulation  . I found this to be the case with other retro handheld consoles , and so I have been using roms that have been specified for Final Burn emulation within retroarch. However I may be wrong , and am open to debate  how to best get a Neo Geo and Arcade gaming  experience from launchbox 

 II am having issues particularly with media and box art ,  that I wanted to get my head around, I think the issue is related to the following points . 

• ROM naming conventions 

For NeoGeo, MAME and Final Burn Roms  I noticed all use a kind of shorthand . When Skraping within LB half are found , though half are not  for example King of Fighters "kof94.zip'  is not found in LB . Though I dont think the ROM is named incorrectly since, other skrapers do work ( Batocera , using Skraper finds most artwork ) . Though the 'kof94.zip'  naming convention appears correct right?  Boxart for the kof94.zip  is found when searching in Skraper.net , so not sure what gives . I have changed the 'skrape as' setting to 'arcade' though this made no difference. 

• Trailing letters after rom name 

I understand some roms have a trailing letter after , for example 'kof97a.zip' this indicates the ROM is for Asian market . However I noticed others such as kof97pls.zip'  and other trailing letters such as b/c/d/e/f  . I guess there are revisions of the game , that are denoted with this trailing letter and/ or number ? If there are revisions for each rom  or there are  have many trailing letters for the same rom , which one do you pick , any particular trailing letter to look for and why?

• Rom Pack Nonclemture

 

If I were to instead use MAME Rom packs , which version is recommended ?  I understand there are many and I think 0.243 are the latest . If using 0.243 Rom pack , there are many different flavours which I have not yet grasped the meaning of :

Merged vs Unmerged 

No CHD vs CHD 

SL Rom ( what is SL? ) 

 

• Platforms and sub platform data 

When I was testing  a ROM pack for MAME , upon importing , there was a really nice platform and sub platform organisation that came with the import, for example from the pack , Launchbox somehow knew which were capcom Cabinets , which were Neo Geo and even gave me different Genres ( though games wouldn't launch ) . I have no idea how this worked , I guess its baked in with the latest version .  I am guessing this is the advantage of using MAME ?  To be honest I would prefer this , if this gives me a good compatibility with Neo Geo Roms and Artwork . Even if it means getting a 300GB rom pack from Archive.org . Though I am just guessing at which version and a bit confused when given so many options for download ( see Nonclemture point)