This could be a small problem with a simple solution I may have easily missed, but when I updated to 4.5 engine and I started a Top Down project the navigation after deleting or moving the walls would not build properly meaning I was unable to advance in a recent project I have been working on. It acts as if the wall is still there blocking the character from moving any further from where the wall used to be, this issue does not occur in the 4.4.3 version so I have proceeded in that engine for now.
Hi DylanTarrant,
I was able to reproduce this and have entered a bug report (UE-4442) to be assessed by the development staff. Thank you and have a great day!