What version of Pro/Engineer (Creo) are you using? Essentially a mapkey is a recorded short cut of buttons/clicks to perform a certain function you repeatedly use.
Click Tools --> Map Keys --> New --> Type the key sequence you want to activate the map key. About Key Sequence - It will select the first one that appears first so if you have one call v and another vv it will always pull v. - Example to create isometric view mine is set to iso Set Name (This is so you know what the key command is) --> You can add a more detailed description if desired --> Click record and perform the desired function such as clicking buttons, setting datums, typing info and so forth. --> Click stop --> OK Now you can type your key sequence and Pro/E (Creo) will perform your defined function. Hope this helps! Let me know if you have any further questions. Check out www.ProEngineer-Help-Tutorials.com or HelpProEngineer on youtube.