Before I bought hardware calibrators, I used this free method…the DVD’s came out perfect.
use photoshops’ Adobe gamma in control panel, adjust each red, green, blue, and save the icm file at gamma 1.8(mac) or 2.2(win) gamma, then setup AE with color management.
you need to give your project’s Working Space a color profile in order to use a color managed workflow (this includes simulated outputs). You can do this in Project Settings (cmd-opt-shift-k on Mac, ctrl-alt-shift-k on PC).
Each file has an interpret color management plus AE has blend color, legacy colors, etc. all these plus you need the exact same codec versions on multiple computers.
plus how you are viewing them back out. Quicktime player preferences could be different too. Use your scopes rather. Do a full render-loop, export/import file, with no color changes, there should be no change in gamma. That way tests for a correct color management setup.