Inca - The Mayan Adventure

Skip to Mayan Temple:
---------------------
Press [F1] at the restore game screen. The password to skip
the first twelve levels will be displayed. 

Cheat mode:
-----------
Enter one of the following codes to activate the 
corresponding cheat function.

Effect                       Code
---------------------------------------  
Display next save password - [Left Shift] + [Right Shift] + [Esc]  
Instant kill enemies       - [Ctrl] + [Alt] + Fire  
Full power                 - [Shift] + [Ctrl] + [Alt]  
Full lives and power       - [Shift] + [Ctrl] + [Alt] + inca  


During dogfights, you can renew your energy by pressing :
[Ctrl]+[Alt]+[LeftShift].

Somebody brought us code 31148226.  
Not much, but a starter...