first step, (either download one of the latest reference files sets OR use the convertdatarebellion.exe with either a batch file or gui wrapper on a COPY of the current game files) get/create a copy of the files in text mode

second step, create a new mod folder in the 'my documents\my games\sins of a solar empire rebellion\mods-rebellion 1.5', then inside the mod folder create another folder called 'GameInfo'

third step, copy from your texted files or reference files the planet.entity files to the mod's 'GameInfo' folder

fourth step, edit each of the planet entity files altering the line that currently reads 'maxSpaceMineCountPerPlayer 150' to 'maxSpaceMineCountPerPlayer 0', saving the file after the changes

fifth step, start rebellion, go to the options/ mods area, select your new mod, then enable it and apply it. shut down rebellion, then start rebellion and actually play a game

hope this helps

harpo

This is strange, I followed Harpo's instructions and lowered the max mine count of my planet entity files (150 -> 75) for testing lag reduction.

I then played a 2hour game, my AI buddy had <50 mines on every planet, except 1 terran world he conquered which had 150, the default cap.

I made another change besides mine count to my mod, a research tech, so I'd know for sure it worked (I just simply changed the cost of one tech by -1 credit to know). So my mod is active, and I modified the max mine count as instructed for every planet type. 

Any idea's why this would be happening? (Even if the planet had the +mine cap bonus, iirc its +25, not +75)

//Edit: Brainstorm maybe

It just dawned on me, the string I edited said max count per player. So since I set 75 as the cap, and its per player, I suppose the original owner had 75 in place, and when my ally took it over he placed another 75?