You can compile your plugins that have been signed with the Xcode debug license in debug or release mode and run them as much as you want. You can even do this on a different machine, when you are okay with a warning here and there. When you want to get up to speed with the C++ SDK again, I would recommend having a look at Getting Started: First Steps, it guides you through all the steps necessary to compile the SDK on Windows and MacOS, and do simple things like adding your first plugin and debugging code.