Okay, but I think it should be good if they had warnings in the log to make the user aware (mostly beginners) to wait and information about how long the process might be delaying(several minutes, more than 5 minutes).
Also, that occurred when I tried to burn a DVD-R in the 16x velocity using the ImgBurn but trying to burn it using another burner program(CDBurnerXP, I don't know if I can quot it here :-))
and with the velocity 8x, the burning worked quietly, without delays. So, I think that you should analize the internal burning algorithm of the program(I'm not sure but I think it must be something like that :-))