Yeah the context is ambignous, but I believe the person quoted the picture had almost same effects onscreen. It seems like hardware bug which is not permanent (because it can be recovered later). Hardware bug nicholes had merged with some internals of KP50 or another root-app (it's mostly software which changes on the device - hardware rarely changes outside disk - and RAM state etc.rather belongs to software state) may triggered bug darodi had happened earlier/more_frequent.

Most people know that nokia devices are really hard to kill (although smartphones/tablets are somewhat more vulnerable than feature_phones/dumbphones), so it's possible that many N900 has nasty hardware bug which is not enough to kill/harm_seriously the device until some software bug happen (and the hardware bug doesn't have to be in all hardware revisions). However something as trivial as loose conections is also possible like darodi said. The problem may for example be also result of some power problems on some graphics-related chip which could be connected with KP50 as it were going to fix power-managment mechanism of N900. Still KP50 is not enough to kill the device - it needs some rare software/hardware state (but some hardware state needed to trigger may be common to some rare hardware revision of N900).

It's better to state "evrything is possible" than "KP is guilty" or "KP is completely unrelated to a problem". I advice people having problem check if another part of their N900 isn't faulty and know there may be something they overlooked. I also advice developers to not rapidly shoot doors if somebody suggest KP50 may be (one of) reasons hovewer the suggestion would sound dumb, because there things about N900 even pali and freemangordon doesn't know (eg. only nokians know such or even them not). On the other side I understand that freaky guy who killed his N900 by overclocking to 1500 and blame the KP50 is reaaally annoying.