isn't it possible to delete text sections once you added them? (cascade)
You may be running into a known issue related to deleting highlighted blocks of text. For example, if the previous block is media (e.g., a map or image) and you highlight text including the first character following the media the DELETE key doesn't work as expected (see screenshot). Does this sound like what's happening in your case?
This issue is on our list to fix for the next release (late Feb 2017).
In the meantime, you can work around this issue by selecting everything in the text block except the first character; then the DELETE key should work to remove the text. Then hit DELETE one more time to remove the remaining character.
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