I think this is correct.
If you leave this as it is, you will also have a dead zone between 7/8 and 15/16 in each direction. Don’t know if you are OK with that. If not, you should also “stretch” the bottom/top tap zones.
In KOReader’s User Guide, page seven you can find a tapzone map. Might get handy at times like this:
http://koreader.rocks/koreader-user-guide.pdf