By default the cyclo ds hooks the media button on the main menu to any nds file named moonshell.nds inside a folder named moonshl.
/moonshl/moonshell.nds
You can rename just about any nds file to match this and dump it there to be launched via the middle media button.
The recent updates (betas) now include new entries to the config.xml file located in the cyclods folder.
/moonshl/moonshell.nds
You can alter this to change what the middle button points to, rather than renaming/relocating your choice of nds file.
As for the gbatempt database file... Huh?
Do you mean the cheat database? If so you just want the file that has the user.evocheats extension. Download the zip file, extract it and place the user.evocheats file in the cylods folder.