Both. Files eventually open. I was able to successfully compile and run the Blink example in the end. But the files take minutes to open.
The Tools menu is never drawn. If I click it the application hangs for about 6-8 minutes.
Also there appeared error messages about contention on the usb-serial port. No apparent reason here, although I opened a second window with another demo program while (I think) I was downloading the blink example.
There isn't any obvious progress while bombing the card that I could find. I was surprised, in the end, when the led started blinking because everything was so slow and the software was not statusing any activity - so I thought it was just hanging again.
This is all a bit frustrating as I have a quadcopter shield that I wanted to buz out on the mega before trying to integrate it on the Blackwidow and the slowness and apparent lack of debug or status will make things really painful.