I think i found the cause of the oil surplus in this mod (0.4). The industrial energy to oil conversion rate starts out at 0.1 and slowly increases to 4 with research. This is backwards. According to hoi2wiki a 0.1 conversion ratio gives 10 oil for 1 energy while a 4 conversion ratio gives 4 energy for 1 oil. So as your army becomes more modern (through industry) and consumes more oil, less oil is being produced, is this WAD? I just reversed the ratios on the industry tech file for this, though I haven't tested it yet.
ps kudos on an excellent mod