The ++++ signs present the loss of contact to the USB during the installation process. Did you try other USB ports?
What's the meaning of "Disk Creator" - what did you do?
I used "Install Disk Creator" from macdaddy.io to build my bootable.
Update:
In the process of installing Yosemite instead of High Sierra as we speak. Also used the "createinstallmedia" command in terminal instead of using Disk Creator (dont know if that made a difference but ...)
Thanks for all your help gentlemen.
Successfully installed El Capitan.
Using SmBIOS:
MacBookPro5,1 - Lets me install MacOS as high as El Capitan
MacBookPro7.1 - Lets me install MacOS as high as High Sierra