A friend passed Zelda, the Twilight Hack worked and I have a new, surprisingly-good-for-being-homebrew channel :)
Second step would be getting backups to boot, but I can't get the cIOS Installer to do its job (install a custom IOS needed by the Backup Launcher). The procedure goes through all the 15 steps fine, but then fails in what appears to be a "finalization" phase. I guess the problem might be that my firmware version is 3.4E; but I really don't want to mess with that using the Downgrader... I've heard it may brick the console, and I'm a coward :P Of course, without that step, the best intentions of the Backup Launcher are not enough :(
In compensation I was able to immediately put the Homebrew Browser to action. It's good to install applications just like you'd do with Synaptics :) There are a lot of applications on the "repository" (wherever that is). Anything really worth installing? Lots of emulators there, but also media players and silly games... I still don't grasp which applications may be "dangerous" for the console and which are safe.
BTW, is anything not on the HBB repo that I should get otherwise? For example, cIOS Installer and Backup Launcher are nowhere to be found... I guess this somehow grants that the HBC universe is not crushed by Nintendo.