In fact, using the camera trick, you shouldn't have to kill LXDE the ugly way, since then you should be able to go back to LXDE with restored keyboard. Except if the stylus stopped working because of some weird cosmic ray event... Upgrading to 0.9.50 is no sweat at all since you don't have to change anything in the image. If you have done some configuations of LXDE, you could however backup the directory /home/user/.config to be able to quickly revert any changes to that.