Good to know that it worked.
And you learned some things along the way that empower you to modify your system to your needs. That wouldn't be the case if you just downloaded a premade image someone else created. (Yeah, I'm preaching a bit about doing things ourselves.
) And you will still get official support in the Retropie forum if you ever need it, since you used the official image.
I plan on keeping all the set on the sd card this way all I need to do is basically in place of say TMNT I just need to rename it to a different ROM file and in theory should work.
To change the game that is loaded at boot? Yes, or you could make one line for each game in the autostart.sh and enable/disable them via prefixed "#" characters, or you could make multiple autostart.sh files (e.g. autostart.tmnt, autostart.pacman, etc.) and copy them to autostart.sh. The latter would be done in the console like this:
cp /opt/retropie/configs/all/autostart.tmnt /opt/retropie/configs/all/autostart.sh
You could even make little scripts to do that:
mkdir /home/pi/bin # create a directory named "bin" in user pi's home dir, this is needed only once
echo "/opt/retropie/supplementary/runcommand/runcommand.sh 0 _SYS_ arcade '/home/pi/RetroPie/roms/arcade/tmnt.zip'" > /opt/retropie/configs/all/autostart.tmnt
echo "cp /opt/retropie/configs/all/autostart.tmnt /opt/retropie/configs/all/autostart.sh" > /home/pi/bin/tmnt
chmod u+x /home/pi/bin/tmnt
From now on, you just have to type "tmnt" [enter] in the console to "enable" tmnt as the bootup game.
(I very much hope that I didn't make any typing errors. If so, feel free to throw it back into my face.)
I noticed that even though I'm not using the full 32gig card the .img file retains the 32gig size for whatever reason
That's because images are 1:1 copies of the whole storage medium. Some imaging programs can determine unused blocks and compress the image accordingly, but it would still be an image of the whole medium – just compressed.
other wise I'd share it without the ROMs... but If anyone reads through this thread is so simple to set this up.
I'm glad that you discovered this, and that I didn't drive you away by insisting that you better modify the official RP image.
I didn't test it yet but the only one I might see having trouble with this is possibly Daphne / Dragon's Lair ?
The emulator Daphne is a little tricky to set up. A good place to start would be – again – the official RetroPie Docs:
https://retropie.org.uk/docs/Daphne/Have fun with your emulation rig. But be warned, they tend to be like model railways that will never be truly finished.