autorun.gpu is a file that you can put in the root of your sd card, if you want mame to run at startup instead of the firmware menu. admittedly, the readme is vague on what that means. if i didn't know, i might assume that meant this is the link i wanted. but in this case it's more like autorun in windows.
the main reason that the information feels scattered is that the software is made by different people. you can't force every single dev to make their programs work the same, or put documentation in the same place, etc. so it's very important that you read the readme that comes with software.
typically the order you should follow when looking for info (for english language) is:
general gp2x info
1. user guide - can be downloaded at archive.gp2x.de
2. gpnewbie.com
3. wiki.gp2x.com
4. boards: stickies, search, ask
specific program info
1. the readme!!!
2. if brand new program, read the appropriate news post on the boards
3. wiki.gp2x.com
4. boards: stickies, search, ask
Diplomat said:
Can i assume none of the emus or apps work with firmware v4.0?
don't assume anything, ever
for instance, that autorun file isn't freezing your gp2x, it just isn't letting you exit, so the menu isn't relaunching. of course, the practical result is the same, you have to restart the unit.
like alex said, the trick is to be specific. even though you just got the thing and you might feel swamped because a lot of stuff isn't working as expected, treat everything as a separate issue, and troubleshoot them one at a time. everyone here will be more than willing to help you with everything you need.
crash course: most gp2x software is released as a compressed file, like ZIP, RAR, or less frequently a gzipped tarball (tar.gz). in most cases you can unzip this to a folder and put this folder anywhere you want on your sd card. in some cases the program needs to be run from a certain place, in these cases it will say so in the readme.
if you want to run a program like gmenu2x right when you turn on the unit, and it came with an autorun.gpe file, put that file in the root of the sd card. if it didn't come with one, you have to make it. it's not hard, but hold off on that one till you get your other stuff working.
hope that helps.