Steps to reproduce:

1. Create 2 hosts;
2. Create a Maintenance period and put one of the hosts under maintenance;
3. Make sure the host that is not under maintenance has a trigger with Disaster severity fired;
4. Create a map with both hosts;
5. Make that map a submap of another.

Result:
As seen in the screenshots, the map with higher level will show that the submap has a problem, but it is highlighted with Maintenance colors (orange) instead of Disaster's (red)

Expected:
Submap highlighted with the most critical issue related to it (Disaster - Red).