Help it says "can only build on blighted area" when it is blighted!

After working weeks on this map, I was playing it as undead. It gives the message 'can only place on blighted areas' when the areas I am trying to build on are blighted. It will not let me build undead structures anywhere.

Its dimensions are 480x480. Every other 480 map of mine works fine. The only unusual thing about its history is that I used Zepir's editor to try to enable more tilesets, but I didn't change anything. I think I just saved it. Any ideas what could be causing this blight placement problem?

I've tried copying and pasting all the terrain and doodads to a new plain map and no luck.

Bueler? .... Bueler?

Any ideas as to possible causes?

Good thought but alas, none of my units have been altered.

T'was the default WE that all of my saving was done in. I was using a custom tileset, but for testing purposes I tried reverting to the standard tileset. Still no luck.

Here is how I tested it:
I placed one acolyte on the map and then ran "test map" from WE. Once in War3 I told the acolyte to build a necropolis. Once the building completed and the blight spread I tried building any other undead structure somewhere on a blighted spot and it says something like 'can only build on blighted areas'. It won't let me build anywhere. What is more odd is that I had a version saved before I saved it in Zepir's editor, and I got the same blight error. That could possibly rule out Zepir's editor.

The only unusual thing I can think of was that I did a lot of copying and pasting of terrain. I'm stumped.

did u mess with game constants at all?

It doesn't work because of how the map stores blight. It remembers blighted areas of the map using an n bit system (I don't know what it is). Therefore, if there is "Blight" outside of a certain area (Past where 256x256 would've ended), the game may change the terrain, but it doesn't register that blight is actually there.