So, I'm trying to replace all values for ambient cell lighting with values of 0 for R,G,and B to get total darkness when no real light source is present (or as close as possible). I am wanting to use a replace via TES3CMD. I'm a little unsure how to insert a regex into the replace function. This is what I have so far, but I have never used windows cmd regex before so I'm not sure how to build an appropriate wildcard. Any help and corrections to this code is highly appreciated: I'm especially confused how to account for the fact that the value of each R, G, or B could be 1, 2, or 3 characters in length (i.e. R=5,G=100,B=25). Please excuse the below if it is horribly wrong and help me, as I really don't know this language. I think ".+" is a form of wildcard based on my google search, but... not really sure.

C:\MyDirectory>tes3cmd.exe replace /AMBI: Ambient: Sunlight: Fog: /AMBI: Ambient: Sunlight: Fog:/ MyESP.esp

Note: I tried this, and also got an "Access is denied" response in the command prompt... ?