ajustements
 

question
just when i open a new scene and i want to execute a mel script, there appear an announcement that the script can not be found. so i open the script editor and use script source by selecting the directory where the is located and afterwards the mel can be found.
is this right that i have always to locate the script or is there a possibiliy that all imported scripts run by starting maya? what can i do?

question
as long as no object is selected in the outliner the dialog closes by releasing the hotkey buttons crtl+o. i don´t like this setting. the dialog should stay open by pressing crtl+o once.

question
how to leave a working operation?
i have read that with the button ~, you can stopp and leave a process.
it doesn´t works at my computer. perhaps because of the german tastatur?
does someone know how i can fix this?

If I understand you correctly, on the first question, you can drag the script name from the script editor to the shelf (once you have sourced it the first time or installed it in the script directory) with your middle mouse button. That will give you access to it from the relevant shelf instead of sourcing it from the script editor and command line each time. You can also assign it a little icon thing with the shelf editor. I do this for all the scripts I use most often and it's a lot handier than having to remember exactly what they are called etc as it's easy to make a mistake with all the case sensitive stuff.

IIRC the CPS tutorial on this site goes through setting up scripts with shelves.