Development topic: http://gtaforums.com/topic/868358-

Introduction:
This mod allows you to edit the colors of four different types of markers in the GTA: Vice City. See the Settings section below for more information. Debug mode can be toggled by typing "MARKERS". When enabled, three world markers and one player marker are created to allow you to test the colors. This mod utilizes CLEO Library for Vice City.

Installation:
* Download the mod (click the Download Mod button).
* Download CLEO for Vice City at http://cleo.li/.
* From the CLEO download, copy VC.CLEO.asi into Vice City's folder.
* If CLEO.asi already exists in the folder, you must delete that file.
* From this mod download, place the CLEO folder containing SEMarkerColors.cs and SEMarkerColors.dat into Vice City's folder.
This mod has been tested only on VC v.1.00 US.

Settings:
The SEMarkerColors.dat file is in plain text with each line representing the color and transparency of a marker type. All lines are in RGBA format using integer numbers between 0 and 255.
* Line 1: Script spheres. This changes the color of cylindrical markers created using opcode 03BC.
* Line 2: Contact point markers. This changes the color of cylindrical markers created using opcodes 0189, 02A7, and 0570.
* Line 3: Highlight point markers. This changes the color of cylindrical markers created using location check opcodes that have their marker visibility set to true.
* Line 4: Entity markers. This changes the color of arrow markers created using opcodes 0161, 0162, 0186, 0187, 0188, and 03DC.
* Line 5: Entity markers glow. This changes the color of the glow around entity markers.