I find that the approach speed set by the MCDU in this aircraft is too close to the stall speed. This means that small gusts can trigger a stall disconnecting the autopilot and triggering the alpha floor (TOGA LK). If you use the performance calculator in simbrief, it will always give a Vapp that is 6kts higher than what the aircraft says it should be. As such, I always go into the PERF page and change the Vapp to a value 6kts higher than what it says. So if it has Vapp of 128kts, I set 134kts and that removes the issue
Not sure on your second point. Are you using sim rate? The v2 doesn't like sim rate very much and it struggles to stay on track