UE 4.11 Preview 4 PrecomputedAOmask

Hello guys,
I have a problem with UE 4.11 Preview4, apparently the PrecomputedAOMask doesn’t seem to work anymore (I have my scene is properly set-up with AO & generate AO material mask activated)
Am I the only one to have this problem or did I miss something with the new version of the engine ?

thanks in advance =)

You’re not the only one, and I don’t think it works in the final release of 4.11 or 4.11.2 either.