Equipping Pyrovision in Mercenary Park after enabling it (although not supported by default, there's a file called mtp.cfg which you can edit to include any map), it'll turn some of the map's doorways opaque. Without pyrovision, with pyrovision. They are still non-solid as you can see. This mostly happens before the first point of the map.
Although it's entirely optional to add this map to your list of accepted maps, it would still be nice to see a fix.