It appears that PHP is causing seg faults within the web server (nothing much new there, it always did look like a buggy PoS ;)) so you may find on occasions that the web site doesn't respond like it should.
I shall look into what, if anything, I can do to fix it (given that PHP Developers usually say 'Its Windows fault' I don't hold much hope but we'll see) but for now, the web server is set to restart itself if it dies, so in theory it won't be down for long if you get problems.
Steve.