Thanks for the detailed report! Weathered Wayfarer actually works: its ability can only be activated while an opponent controls MORE lands than you (any opponent counts). When that's not true, the ability isn't available, and since tapping the card gave no feedback, the game simply moved on to combat, which is why it looked like it could only attack. That part was a real problem, and it's fixed for the next update: tapping a permanent whose ability can't be used now tells you why (the card's own condition, that it just came in, or that it's already tapped).