The server has been updated to 1.12.1. The is some incompatibility between 1.12 and 1.12.1 and we want people to be able to use the latest version. Forge and Optifine are out. Optifine's website is experiencing issues, so you can download it here: http://optifined.net/adloadx.php?f=OptiFine_1.12.1_HD_U_C5.jar
Honestly, the idea of calling it quits (maybe temporarily) has been brought up more than once. Catbox01 correctly called it when he questioned if we would have the time for setting up an updated server.