So with OGL 1.2 issues--which I am not discussing here--I thought some notes I had considered might be useful in helping D20 players learn the D6 system (which is ultimately pretty simple), I have a few notes I had started to take on a conversion of D20 abilities to D6 attributes. I have only a small fraction of that conversion done, Maybe I will release a few points in Ogl 1.0a before it goes out of use, but I thought some feedback would be helpful, this is very rough.

D6's SRD can be found here: http://opend6project.org/.

A variation known as Minisix (I think Minisix is sort of like the Basic edition of DnD before AD&D) can be downloaded here for free: https://www.drivethrurpg.com/product...-Bones-Edition

conversion of ability scores
DnD Attribute Dnd Bonus Rank Die Code
20-21 5 11 4D
18-19 4 10 3D+2
16-17 3 9 3D+1
14-15 2 8 3D
12-13 1 7 2D+2
10-11 0 6 2D+1
08-09 -1 5 2D
06-07 -2 4 1D+2
04-05 -3 3 1D+1
02-03 -4 2 1D
00-01 -5 1 1D-1

So if a character in DnD has a 15 in strength, in D6 that would translate to 3D.

Add your Compentency bonus to any weapons groups or skills you on a 5e sheet.

SKills with an A are being treated as "advanced" skills which is a factor in the old Star Wars RPG which may or may not have been carried over into OpenD6. My ideas was to use these as "class skills" as a player would choose a class for some bonus skill dice, but would not be allowed any other Advanced skills at character creation.

Races are covered in the OpenD6 SRD.

Attributes and their Skills:

Strength
Athletics, Lifting, Heavy Weapons


Dexterity
Archery (A), Acrobatics, Dodge, Simple Weapons, Martial Weapons (A), Slings, Ride, Sleight of Hand, Stealth, Thieves Tools (A), Thrown Weapons, Unarmed Combat

Constitution
Concentration,
Stamina (saving throw)

Intelligence
History (A), Lore, Literacy (A), Memorization, Nature, Religion
Languages: Languages

Wisdom
Animal Handling, Crafting (A), Insight, Investigation, Medicine (A), Perception, Survival
Will: Will (A) (saving throw)

Charisma
Deception, Intimidation, Musical Instruments, Persuasion, Sings

Extranormal
Skills

class kits
For new characters instead of transferred ones, here are some sample kits I was playing with: I fighter would add as many "pips" to the approrpiate skill, classes would be advanced with either a homebrewed experience or by advancing the highest levdel skill (per D6 advancement rules) but multipying it by 4 rather than three (meanng that your fighter becomes better at all figher skills more rapidly than if he started trying to learn thief skills.

Class Kits
Basic Commoner
Minimums: none
Skills Lore +3, +3 area Knowledge (local), +3 Crafting/agriculture/medicine, +3 simple weapons
Special none

Fighter
Skills +3 Martial Weapons, +3 Player’s Choice: Archery, Slings or thrown weapons, Players choice: +3 to Athletics, Acrobatics or ride. Players choice +2 dodge or unarmed combat.
Specialization Pips: +3 to a specific weapon added to either Archery, Martial weapons, or Heavy Weapons
Specials: None.

Thief
Skills: +3 Thieves tools, +3 Stealth, +2 Sleight of hand, +3 Perception
Special: sneak attack damage 1D

Wizard
Attributes: +1 Extra Normal: Wizardry 1,
Skills: +3 Arcana, +2 History, +3 literacy, +2 Will


(Wizardry, Cleric, Druidcraft, Sorcery, psionics and Warlock would all be "Extranormals" you can use the DnD schools of magic as the "Skills" and convert spells using the rules provided in Open D6, though the die codes may mean some relatively low level DnD spells are relatively difficult D6 spells and a few higher level D20 spells might be easier in D6). ONe thing that can balance Martials and Casters in D6 is that extranormal skills and attributes cost twice what normal skills use.