You know, it seems that you are right. I've checked the schedule on a different web-site and according to it on Thursday 13.00 and Saturday 16.00 it will be live too. But tonight I tried the links at about 23.00 and instead of tennis there was dancing and then something else. Actually it's not a sport channel that Russians in Russia watch, it's more for Russians abroad, so I don't know what they usually show and how the real coverage fits the published schedule..
But I've found another link! http://video.sportbox.ru/
They promise live coverage every day from 11.00. Just click on the picture with 'Теннис. Кубок Кремля' and Davydenko or the line with the same words in the schedule on the right. Hope it will work.