I had problems with the fresh install as well, here is what I did to get it running with Tier 1 apps.
1. Installed fresh Raspbian Stretch 2018-03-13
2. Downloaded and unpacked AGKPi 2017-09-25
3. (Terminal) sudo apt-get update
4. (Terminal) sudo apt-get dist-upgrade
5. (From start menu) reboot
6. (Terminal) sudo apt-get install libsdl2-dev
7. (From start menu) reboot
8. (Terminal) sudo rpi-update (This seems to be the essential part as it also updates "Video something". First time I did this with the fresh install, it would not boot afterward, but it seems like the firmware lives on the SD card, so a new install made it work again)
9. (From start menu) Shutdown, wait until disk LED stops blinking, unplugged power, waited 10 sec, plugged power back in.
10. Compiled a simple AppGameKit Tier 1 app and ran it from terminal like this ./Core (Core being the app I ran). (I use ./ to get output to get an idea of what goes wrong)
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