That is rather distressing to hear. We sure did a lot of testing in the hope of not getting a report like this one, but I guess we must have missed something. Can you post a screenshot of what Skyline looks like when it "locks up"? By locks up do you mean that the UI becomes completely unresponsive, or just that it never finishes importing?
Also, for a first look, it would be great to see if we can reproduce this with your files here on another computer. Maybe you could also try to reproduce it on another computer there also. I would suspect that this is a computer specific problem, but if it happens on any computer, then it will be a lot easier to get fixed.
I will contact you about sending use files.