Sorry for the late reply.
If I read this correct. You have 64x64 pixel panels, With a tile count of 7 wide by 6 tall with an invisible strip (dead space) in between. so that would bring the total tile count including deads to 13 wide by 6 tall (every other wide tall is a dead tile).
This would bring your total pixel count to 832 x 384.
The nearest friendly resolution to this count would be 1024 x 768.
If you center your 832 x 384 wall into that composition it would look like the mapping I attached. You shouldn't see any red when you throw that image up.
(I use Nova, so if you use anything else, I wouldn't be able to assist in that)
In your processor I would set your wall start position at: X: 96 , Y: 192 (1024-832/2 for X) & (768-384/2 for Y)
Basically subtracting your wall pixel count from the composition resolution then dividing that number by to so you can center your wall into the overall composition.
Then I would make sure to add your dead tiles in between your active tiles.
Once that is done, Open resolume and set a comp size of 1024 x 768 and in your output create multiple slices if needed, otherwise just have a single fullscreen slice. and throw up the map and you should see a nice white outline on the edge of each screen and numbers to make sure it is mapped in the correct order. If you see any red, or the numbers don't match something was done wrong.
There's 100 different ways to achieve the end goal, this just happens to be my method.
Hope this helps you out in some way or another