The time signature does not matter in a midi, because a midi is a series of digital events on a time clock. If you were to play a waltz on two handed piano for example and record it on midi it will play back exactly as you played it.
Styles are labelled according to their genre, and of course if you are using a style, it has to be in the time signature to match what you are playing so everything lands on the right beat. But that is not the case for a midi. Ignore the time signature,
Mike