is GoldEd running? this one should open the port, another application may ask for.
i never used CubicIDE, just installing at the moment.
Edit: you can look with
ARTM if the port is open, once the error occures.
the ide is based around golded ( optionaly cygnused - while installing). so there might be a conflict with another program, blocking the port, not sure, if those are exclusive once used.
i only installed the demo, reboot, and run the ide. i could see the GoldED.1 port listed , with artm.
anyone with more knowledge?