BatVink,
thank you for clarification.
Actually I found solution for my problems - it is not related with agk - it is some QT-bug in xubuntu. Because of it when I hold a button, object/sprite movement stops after some time. If someone reports it, please remember to mention, that it is a bug and workaround for this is to disable repeating settings for key or tell me about it. I will solve it someday.
Regarding AppGameKit itself - the main feature is crossplatform and android included. I don't need to learn some code to port to windows for example. But I only have text editor - that is not something expectable. But now it is OK for me.
Unity is not available natively for linux so I don't consider using later.
Moreover I saw some example showing that I can use high resolution with small sprites and then get huge scene.
So everything is OK now.
Regarding original topic purpose in the "Utilites" folder there is a placement editor folder. Unfortunately it doesn't work on Windows nor on Wine, probably I just need to install the program from scratch on Windows or on Wine then Placement editor will work.
There is a "Viewer" folder. I can compile it but it shows only black screen.
Both viewer and editor shows this string:
Virtual joystick 0 does not exist
Also viewer requires some files created in the "Editor" because it ask for this: Failed to open file for reading export.txt
Because of this string:
LoadFromPlacementEditor ( "export.txt", "virtual" )