Conditions can be removed prior to expiring in a number of ways either by the bearer or ally. In your first example the condition prone is being removed early by the enemy. The ruleset however is not designed specifically for a 1v1 combat encounter. I offer a more typical example within this game.
Turn 1 Enemy 1 attacks doing 8 damage.
Turn 1 Player 1 hits Enemy 1 with topple for 2 damage applying the prone condition.
Turn 1 Player 2 now having advantage on enemy 1 (turning their chance to hit from 50% to 96%) lands their weapons special ability doing 30 damage and applying the burning condition.
Turn 1 Enemy 2 douses enemy 1 with water (ending the burning condition).
continue.....
Still simplistic, but...
Conditions are handled differently form the PnP 5e ruleset. Agree or disagree as you will on how the conditions work in BG3, but any attempt to claim that the way conditions are implemented is broken fail considering the rules apply to all combatants. Any perceived advantage the enemy may encounter, your party can claim as well.
Aside from that some things are indeed not working as intended. At least fixes no longer require you to call a game company within a short time window and pay, at the very least a shipping and handling charge, so that a working version will arrive in 6-8weeks.