How can you make the openings explorer work for other players?

Hello everyone. I am a volunteer chess coach for my old high school chess team and have been trying to look at some of the club members games through the openings explorer. However when i try to do this only one or two of their games will import, which isn't very useful. I have tried clicking "Analyse" on all of their recent games and have waited overnight since for this to have any effect, but this is to no avail. 

Is this a bug, and if so how do i fix it? Or does the feature just not work on players without premium memberships?

Do they play games shorter than 5 0?

Some of them play some games shorter than 5 0 but most of them are 10 0. The first person i checked had played more than 2-300 rapid games. Apologies for taking so long to respond. 

It is a premium feature.  I asked one of the staff.

Can you tell me the name of one of the members you tried to get it to work for?