It still has the simulator as before but it's a bit harder to configure it.
1. import the original project as a "v8" project, it should create a new MPLABX project with the same name. File>import/MPLAB IDE V8 project. The original is untouched.
2. under 'File> project/properties' select the simulator as the hardware tool. You can also select hardware debuggers here too.
3. under 'window' you should then see various simulation tools, much as in MPLAB v8. Under Window>Simulator I found 4 options:- Stimulus, Analyzer, IOPin, Register Trace. I chose Stimulus.
4. use the hammer icon (or F11) to build the files. I did this & the build was successful.
If the build is successful you should see 'reset', 'step', 'step over' and all the old debugging icons at the top of source window. You can select which registers to display and the display format in the output window and you can set/disable breakpoints by clicking on the source line number in the left margin.
Brian.