Can you downgrade 2.0 clip files back to 1.5?

I don't understand exactly what happened, but I restarted my PC today and I turn it back on to find all of my clip files automatically converted to 2.0 compatible versions. I don't have 2.0, and I'm not convinced to pay for a new license. But I don't know if I have much of a choice now that everything is in this new format I can't access, so is there a method of converting them back to 1.5 files?