I have installed the item but I cannot perform the landing challenge.
Sorry for my bad english. All installed, up to date on the right but unable to proceed.
HI,
Maybe remove all add on from your community folder, and start again FS2020…
This challenge is not one of the most easy 
I have already cleaned up the community files because of stuck in the loading interface 
This error with the landing challenge is caused by the FlyByWire A32NX mod since the last update.
You have to remove it if you want to try the challenge.
I did the challenge with the original airbus 
…and then i installed the mod again as it’s easy to create our own landing challenge.
As explained above, the issue is that the A320nx mod will not be compatible with the A320 landing challenges at this time (I believe to facilitate a fair challenge for all of those competing for their scores). Remove the mod from your community folder and it will work.