We have information here on using cloud functions in MAMP PRO
http://documentation.mamp.info/en/MAMP-PRO-Windows/Settings/Cloud/
http://documentation.mamp.info/en/MAMP-PRO-Windows/Settings/Hosts/Cloud/
Additional cloud troubleshooting information can be found here
http://documentation.mamp.info/en/MAMP-PRO-Windows/Troubleshooting/Cloud/