Honestly, I'd say to save your money and if you wish to donate, simply play the game and enrich the world with your presence. If you are more technical based, then hop on the bug tracker and see if you can be of service with help findind solutions to bugs and what not. Or if you are more of the artistic type then there are always textures/items to be modeled/ etc etc to be done. Monetary donations are pretty much useless atm, and pretty much will always be. Only reason the donate option is there is becuase after years of people refusing to not want to donate money, they finally gave in and added a donate option. Only thing money will ever go towards is maybe if something should happen to the server or what not, but everything is donated to us out of good will, so that will probably never be an issue.
As for the updater, it is currently disabled, and s not needed to play. A fresh install of the .3.20 client will allow you to login and create your character.