To edit your microKorg with Patch Base, you'll need to make sure that your synth is set up to send and received sysex data.
Also, if you want to change Global settings or save patches to the microKorg's memory, you'll need to make sure write protect is turned off on your microKorg.
The microKorg is slow to process updates to its Global Settings, so sometimes when you change a continuous control (like Tune, Transpose, etc) in Global, the final value you set won't be read correctly by the synth. If you notice this happening, just tap the Send button in the upper right of the editor to re-send the Global settings from Patch Base to the microKorg.