How can I reach the UI to configure the autostart applications in Ubuntu 11.10? Please don't tell me, I have to do it using the terminal or creating a starter on my own and please don't tell me, it is gone!
Try using the Startup Applications application. You can find it either by searching for it (both Unity and Gnome Shell allow you to quickly search for applications), or in the Other section of applications (this section you can access again from either Gnome Shell or Unity but also from the classic applications menu in Gnome 2.x)
Applications may be startup in other ways, such as commands in scripts and etc. It is probable that the application's startup you are trying to edit is not accessible from the application I suggested to you.