A few ideas:
1) Clean out the membership roles of those no longer playing WGT. 52 of your members have not played in 2016. Remove them so you know who you are trying to work with.
2) Find out what the remaining members of the CC would like to keep that core group motivated. They, not the ones that have not played in a year are the ones that matter.
3) You do not have any top tier members so this one might be hard to accomplish, but most players will stay motivated if they feel they are improving. If you had even one Legend that wanted to mentor the newer lower tier players that could help. Absent that find good tips and advice on the main forums and hot link the posts in your CC Forum.
4) There are some trophies you can put members names on that are as much of a reward as credits or sleeves of balls. Develop some recognition program - like most CC Tournaments played each month, most improved player of the month, shot of the month or whatever you like.
5) Start some tournaments that are ongoing that one has to compete in weekly to come out on top - you know tournaments that are "must play" not just another CC Tournament.
6) Have some Fun. Have tournaments where members get a good laugh or two - like irons only or starter club tournaments in Match Play. You could have a beat the Owner Tournament or whatever. Get creative.
7) Liven up your CC Forum! Last post in the CC Forum is now a month old. A number of new members joined in that month and there was not even one welcome message to them. The CC Forum should be the first place every member wants to go to when they log into WGT.
8) Lead by example, if you play nothing but CC Tournaments every day - members will follow suit. If you just go out and play your own single play match - they will follow suit.
Finally, being the owner of a CC is a full time commitment, if you do not have 2 - 3 hours a day to give to being an owner (note I said being an owner not playing WGT) then it is going to be a long hard road to develop a sense of belonging to the CC among its members.