It says "AGA is required for this game" (e.g. Amiga 1200/Amiga 4000).
My A500 mini runs AGA games, not sure what is going on with your mini. It's supposed to run Amiga 1200 games, despite the name.
I've tested and it fully works on my A500-Mini. Check video at the end of this post.
I recommend that you don't rename it from the original scorpion_dev.lha name. Also, you should do the config below, which tells your mini to use AGA chipset, among other things.
1. Copy scorpion_dev.lha to your Amiberry device into THEA500-Games\
2. Copy the following lines into THEA500\whdboot\game-data\whdload_db.xml after the whdbooter element is opened (should be line 2):
<game filename="scorpion_dev">
<name>Scorpion Dev</name>
<subpath>scorpion_dev</subpath>
<slave_count>1</slave_count>
<slave_default>scorpion_loader.slave</slave_default>
<slave_libraries>False</slave_libraries>
<slave number="1">
<filename>scorpion_loader.slave</filename>
<datapath>data</datapath>
</slave>
<hardware>
PRIMARY_CONTROL=JOYSTICK
PORT0=JOY
PORT1=JOY
FAST_COPPER=FALSE
JIT=FALSE
CHIPSET=AGA
SCREEN_AUTOHEIGHT=TRUE
SCREEN_CENTERH=SMART
SCREEN_CENTERV=SMART
</hardware>
</game>
Thanks for your words. I also got some flicker here and there on my mini. They don't happen on a real Amiga (check video).
I got more serious issues on other games such as Risky Woods (flicker and also stutter), I think that I reported it to the related people on Discord. The upcoming THEA1200 full size next year likely won't have these issues if it uses FPGA instead of Raspberry Pi or a stronger Raspberry Pi that enables it to handle games that make heavy use of the Amiga's Copper coprocessor.