Yes, a CME could last 24-48 hours and so would give most of the Earth time to enjoy it.

I'm sceptical about the claim that all the transformers would melt, powergrids have a lot of safety systems to protect them from natural events and idiots. The huge blackouts seen in the US and Canada are precisely because of this - at the first sign of anything bad happening systems disconnect everything - leaving people without power, but preserving the infrastructure.

It takes a deliberate level of stupidity to force the system to damage itself - Enron and unregulated markets for power transfer are more effective than an EMP.