PanasonicLUMIX G X Vario 12-35mm/F2.8 ASPH./Power O.I.S./H-HS12035 - International Version (No Warranty)

What is meant by International version???

Can you put ND filters to this lens?

Does it come with a booklet with instructions in English and also the protective caps?

I want you to explain to me what "no warranty" exactly means. if the lens does not work properly when i get it, i can not do anything? thanks.