Alternative for Challenge as section header

Solution 1:

We use "Special Considerations" for our similar section header. It allows everyone to save face, and it allows us to detail some of the finer points that other sections may miss.

Solution 2:

If this section contains "gotcha" warnings not covered elsewhere, I think "Challenges" is a fine heading (or "Implementation Challenges" if that level of specificity applies to your situation). If this section calls out information that is covered elsewhere, e.g. you talk about requirements-based challenges in Requirements and design/implementation challenges in Technical Solution and so on, then perhaps "Summary of Challenges" would be better.