The meeting remains cancelled till further notice

The first and third are fine.

"Cancelled" is a perfect participle, also called a passive participle. It is used adjectivally in sentences 1 and 2. It is purely terminological preference whether, in sentences 23 and 4, it is described as part of a verb phrase or as a participle used adjectivally.

Many will say that sentences 2 and 4 are equally good as 1 and 3. I prefer using the present tense to make absolutely clear that the cancellation applies now as well as to an indefinite future. I may be excessively fussy.