Where are the screen configuration files stored?
How do I get back to the default screen setup?
 
Where are the screen configuration files stored?
 
All IpBike files (rather than files from libraries like osmdroid) are stored on the sdcard (or internal equiverlent for devices with no SD Card.
/Android/data/com.iforpowell.android.ipbike/files/ is the root directory for IpBike then landscape_screens/ and portrait_screens/ are the directories with the screen setup files.  They are human readable but I would not recomend manual editing.
 
How do I get back to the default screen setup?
 
There is no automatic way to do this in IpBike but if you just delete the directory where the files are then it will be re-made with the default files coppied in.