Hi Dimitris,
Yes, we are using both: static pages and custom navigation menu items. I can see MNI have the same context and path as before upgrade.
I did a test in a 3.1.2 fresh installation:
- Created a staic page “Page1” with path “p1”
- Created a NMI “Page One” of “Custom Page” type and path “p1”.
- Enabled NMI “Page One” in Primary Navigation Menu
When clic “Page One” menu, static page “Page1” content is not shown