Description of the Bug
The Routing Table becomes invalid (red cross on Routing Switch Actuator Motor or Cart Detector - Routing, with error: 'Unrecognized Keyword ""') if you save it with a blank page.
You need to completely delete all text in the table then save then retype the statements for it to work again.

To Reproduce

1. Open Routing Table
2. Type any valid syntax such as 'Dest=Test'
3. Press the right arrow to move to the next page
4. (optional) Press the left arrow to move back to Page 1 and note that it still says 'Page 1 of 2'
5. Press 'Done'
6. Put Routing Table into any block that accepts it and see it will be invalid (red cross on Routing Switch Actuator Motor or Cart Detector - Routing, with error: 'Unrecognized Keyword ""')

Expected behavior
On step 3 of To Reproduce if you then press 'Done' the Page 2 should not be saved, so the book has 1 page that is valid
OR
On step 4 of To Reproduce if you press the left arrow the 2nd page should be deleted, so it does not have 'Page 1 of 2' in the top right, even though page 2 is blank

Logs & Environment
forge-1.12.2-14.23.5.2847-universal.jar
railcraft-12.0.0.jar
as part of the Mech & Magic 3.1.8 Modpack.
(let me know if you need full latest.log)

I believe the code for this function is:

but not sure on how to fix it