builders playing up since upgrading to 7.02

Since I upgraded my installation to 7.1, I cant load the Navigation and Member menu builders, it says

Also, the Pages Blocks builder starts to work, but stick at "loading..."

Can anyone help?

Thank

I got the same thing!! My hosting comany is telling me to revert back to a back up of my site....

I am trying to restore from backup but even that is proving difficult

anyone done this before?