Error while compiling HardcoreWorkbench: No overload for method 'SendNetworkUpdateImmediate' takes 1 arguments | Line: 66, Pos: 37

It looks like the method changed. I think all you need to do is to delete the argument in the method. Instead of "vending.SendNetworkUpdateImmediate(true);" set it to "vending.SendNetworkUpdateImmediate();". Then the plugin compiles successfully.