Some of you who might have played Marathon back in the day and have come back to it with AlephOne might find there are quite a few changes made to the game's engine and overall look, especially in the first installment. So for any of you looking for an experience closer to the original thing, here are the best add-ons and settings to use!

First of all for M1A1 (Marathon 1) is the 'Classic HUD' plug-in, which restores the games' original HUD from the Macintosh version as opposed to the HUD that looks more like that of the one from the two sequels. You can download it here (installation instructions are included in the 'ReadMe' contained in the main folder):
http://www.simplici7y.com/items/marathon-classic-hud
There are also these two plug-ins for M1 that are not particularly necessary, but make it closer to the Macintosh original (installation instructions are included in the 'ReadMe' contained in the main folder):
M1A1 Fixes - http://www.simplici7y.com/items/m1a1-fixes
Marathon QT2 Tracks for M1A1 - http://www.simplici7y.com/items/marathon-qt2-tracks-for-m1a1
As for the best settings to use (and this is for all three Marathon games), here they are.
At the main menu, go the Preferences and then to Graphics. Here, change the renderer to OpenGl (Classic). The other settings on the screen do not matter, though you can change the resolution to 640x480 if you want to be really retro. Now click the Rendering Options icon. Here, untick all the boxes toward the top except for Colour Effects and Static Effect. Also turn off Full-screen Anti-Aliasing and turn down the Anisotropic Filtering all the way (I recommend you turn on VSync to avoid image tearing). Now you go to Advanced, and put all Texture Filtering options to None, and Apply!
You are now ready to enjoy a classic Marathon experience!
- TheMoonChef