I can't reproduce that, however, I'm not including the specific step of restoring an ST3 Full Backup into Build 1897, which may (or may not) be a critical factor.
But in general on 1897, I can use the zoom buttons just fine and scroll manually.
@DickyDutch a few quick simple things:
- Reboot iPad - still same?
- Create a new song (i.e. not using a restored song) and import a lyric sheet (i.e. can we remove/confirm the import as a part of the problem) - same issue?