Way to set fixed background size for subs in SubtitleCreator or DVDSubEdit?

[blue2]

Hello. I know the maximum subtitle width can be set in SubtitleCreator, but is there a way to set a fixed width for the background the subtitle appears on so that it is always a defined width irregardless of the length of the subtitle? For example, so that the background for a short subtitle line like "Hi" will extend beyond just the width of those two letters? I'm using SubtitleCreator and DVDSubEdit, and have not found it, but perhaps I missed it.

Many thanks.

[blue2]

I guess no one knows the answer to this question. Oh well...