I clean out the cache regularly.
But the good news is I have found a way to be able to play the PB CTTH again. I went to my Score History and found a previous CTTH game I had played on the PB course and clicked on that game in my Score History. That brought up the following
http://www.wgt.com/golf-tournaments/leaderboard.aspx?id=7ce9445575c9405fa2d1a31b013f11d
I'm not sure if that link will work for others as it's a link from one of my games. However I was able to click on PLAY NOW and play the PB CTTH game again. I also bookmarked it just in case. I mention that in the hope that it may help others who are/were having the same problem that I was having in trying to play the PB CTTH game.