Can also confirm it works on pi 4, thanks mitu

TriggerHappy kicks a$$ .. thanks for pointing it out

@Dj-EKI If you'd like that combo to open the menu, then open RetroArch from the RetroPie system in EmulationStation, set the option and then save your configuration.
To leave a game, you'll have to use either a Hotkey + Start - which you don't want - or disable the Hotkey and choose another button for the exit hotkey. Pressing that button will automatically exit the game.

@mitu for example

I am going to change the button layout for Alien Storm for the Sega Megadrive

I have started the game
Entered the RGUI menu
Go to controls
Set the buttons up accordingly
I click on save core remap file in the controls menu
I have the message "remap file saved successfully"
I resume the game
The buttons work perfectly
I exit the game back to the game selection menu
Restart the ROM
And it works perfectly.

I don't believe this. It has worked. The problem was I was saving using the "save core override" option when I should have been using the "save core remap file" in the controls screen.

Thank you so much for everything Mitu. No doubt I will encounter another problem where you can rescue me again. Thank you and have a nice day my friend.

@Dj-EKI map z to left trigger I believe

@roslof I agree. It can probably be done on retropie. I run space invaders with the mame2016 core via retroarch.

SOLVED!- it was in the coding- I had buttons double-coded so to speak and had a bunch assigned to R_X/Y plus&minus (input_player1_r_x_plus_btn = "5" for example) as well as what they should've been assigned. HUGE weight off my back- I've been poking around like a blind squirrel.

@quicksilver Thank you very much, after removing the # in the config, it boots perfectly now.

I know this is quite old but maybe someone can point me in the right direction. I am trying to set this up again using a new pi 3 and RetroPie 4.5.1. I get the same thing, emulationstation doesn't see the controller but it looks fine running the jstest program. What can I do to allow the controller to be used in RetroPie.

@mitu Yes, on Windows it works normally. Anyway, thanks for your help. I'll try to find more information all over google.

@niners4952 Note that the Pi4 support is still in a work in progress, so you'll have to perform a manual installation (https://retropie.org.uk/docs/Manual-Installation/). Even so, expect some things not to work or have bugs.

@jackpage43088 https://retropie.org.uk/forum/topic/3/read-this-first

You're welcome here but please install RetroPie from our site. We can't (nor want to) support a modification of our software provided by someone else.

It's against the licenses of software included in RetroPie for it to be sold or included with a commercial product.

Rpi4 support is still being worked on. It's not officially supported yet and many/most of the images out there are hacks also and don't implement things correctly.

@Sanctus Alas, I don't know Batocera or its directory tree at all. Maybe you should ask this at the Batocera forums with reference to this thread. I guess you are the Sanctus over there, too?

Should I run the remaining "Remove the Old folder if it exists" and "Use Alternate background for main menu" items?

I don't know, you'll have to ask the theme author what those mean.

I tested the theme and it works fine at 640x480 (video & all), unfortunately I don't have a way to output 320x240 to test it at this low resolution.