In the latest release, 4.0.8, the CSS was reorganised into one singe highslide.css file. This makes it easier for all implementing Highslide, as the relative graphic paths don't have to be updated. The downside is the increased weight, but the file is well commented so removing parts of it should be relatively easy.
The latest release also includes a very clean looking new example with the caption text overlaid on the dark page background.
That was one of the nice surprises in version 4 - I no longer had to give my users a slider to select extra padding on the bottom margin to accommodate longer captions.
I never had any way of predicting how many lines of caption material there would be, since line-wrapping would produce different results depending on monitor resolution, font size chosen, etc. So, that was always a "take a guess" setting. Happy to get rid of it.
Yes me too. As for the free-floating caption, it is not really a new feature. I was just experimenting with the CSS when it struck me that I could set position:absolute to make Highslide ignore it's height.