Thanks for playing the game! I'm aware of the mana collection annoyance, what you can do to remedy that is to click on an empty area and drag over multiple mana orbs to collect them. (In other words, drag/swipe your mouse across mana orbs while holding down left mouse button, this will collect every mana orb you drag your mouse across.)
I am also actively developing and will update the game after the jam period is over so feel free to check later for a better tutorial and more responsive controls!