I think we both may have missed something. For Linux we build from source or use a repository to install MAME. Installation from a repository does not always create the full directory structure. When installed from a repository the data files are often not installed at all or are not kept up to date...

I've used MAME for a long time, and MESS before it was rolled into MAME. One of the problems that affects first time MAME users is directory setup. We have ROMs, CHDs, Software Lists, Extras, Media... I understand how to set up MAME but many people new to MAME or people who would like to use MAME st...