Ah - it sounds as though the leaderboard may not have loaded. The authentication thing is for the benefit of anyone who wants to use a gd.games account: it’s not necessary if you simply type in a name. (In hindsight I should possibly have cleared the banner from the screen during the leaderboard load.)
I just looked up Double Wires and think I played it back in the day! It’s entirely possible it was a bit of an influence on this.
If I come back to this idea, I think I might opt for a single arm anyway (the bits that really benefit from having two seem to be what gives people the most trouble). Someone else suggested having more vertical space above the player, which I think would be a good idea, and if the whole thing ends up being portrait anyway I figure it might be worth aiming for controls that would suit a phone touchscreen.