I have Instant Text. When I want to save an entry, I highlight what I want using a space after the text, do a control C to copy. I do an alt plus the equal sign to bring up Instant Text. I do a control V to paste it to Instant Text, click on the format tab to save any formatting, give it a short abbrevation name, and put save or add to (whatever it is). Then, it comes up as I saved it. I am not quite sure what you are doing wrong, as I never had that problem when I do it this way.
Try to save something else rather than S1 or S1 because I know that at times when I am doing a listing like 1. and 2. on the next line, S1 or S2 come up. I think there is an abbrevation already in the Instant Text with an S1 and S2. That might be the problem.
Let me know.
Pat