We've raised this already via the Marketplace Team but you may not be aware... The Ground/Water based animated SimObjects are not being refreshed in relation to the player. The impact of this is that when you start your flight you will see intended SimObjects but they will fade out as you move away from your start position. New SimObjects that are supposed to be there will not appear in front of you or around you for the rest of your flight. We are unsure if this was pre-SU5 or new. This doesn't affect wanderboats. We suspect this could have a big impact on your Top Gun expansion.
On a related note, changing the time or weather slightly seems to give the Sim/AI engine a 'kick' and will refresh a few (but nowhere near all) of the intended SimObjects around you. Please can you investigate and provide feedback on whether and when it will be rectified. This is currently having a negative impact on player experience our products.
Thanks for your time,