Thanks for the extra info fourroses666, I feel more confident about it now.
Good advice about the backups - I agree, very important during an upgrade.
Thank you for the heads up on the phpthumb call. Your second way is the way I have been calling it but that is very handy to know.
Thanks for confirming MrHaw. Good advice.
To setup a local webserver is simple and perfect for a usb-stick. Now when debugging you have the option to edit server settings you might not have on your web host.
I'd love scaring people into this!!
Ha ha, one day I might try that if I can find a good tutorial.