remember to do a git pull before you push!

Hi Jan.

I've patched up the rendering code on your branch - the way that the rendering system works is quite messy, so it was simpler for me to fix the bug(s) myself rather than leaving it to haunt you for the rest of the summer.

Unfortunately, whilst patching the problem with the arrow rendering, I realized that there is a fairly serious issue regarding the way the arrows are rendered. Take a look at JAL-897. There are a bunch of comments on several other bugs, too.