Is a topic about a dice-system mechanic for a tabletop RPG legal for this forum?

I am a board-game designer (2 games presently in sales) but I am having issues with a dice-system atm.. wondering if it's OK to post the problems I'm having here or no?

Ok, Sheldon set the WABAC..

Like many GMs, I've been using my own RPG system for a great many years now.

Version 4.0 of the system was quite good, and is in use in a few gamer groups all around. 4.0 worked on rolls of d% vs. abilities up to 100 (normally.) There was a table which helped you figure the % of anyscore, or what result would be what % (inverse lookup.) For example, if you rolled 34 with a skill of 75, the result was 22 (or 2DG) or when a character was hit with 32 damage with a health of 89, you were able to look up that it was 36% (or 4DG.) However, I was unhappy by the fact that 4.0 required the use of a table, and so I tried to come up with a better one.

Version 5 (V) replaced the table with dice. You rolled dice (d6) = skill, and any dice over 4+ was a success, where skills were from 1 to 10, so the results were from 0 to L where L was the skill level. This I used for a few years before I began to see a huge bell curve in the results. Simulations showed a huge bell curve (eg., if you rolled 6 dice, you got 3 a LOT of the time.) A mathematician husband of one of my players informed me that ANY time you roll multiple dice, you get a bell curve - the more dice, the worse the curve.

I went through a pile of other versions, 6, 7, 8 .. I lost count and the version numbers ceased to have meaning.

The one I have been using for the past few months was that you rolled a dice that gave a result from -2 to +2 added your skill, and subtracted difficulty, where stats were from 1-10. This is quite linear, and gives good player satisfaction (some will recognize it's like Fudge withuot a curve) but I had not considered range. With a dice that rolls +2 max, if you encounter something with a difficulty 3 levels higher than your stat, it's flat out impossible to succeed.

I then said, "Well, what IS the range I want?" and decided that a score 10 levels higher was limit. Therefore, I made the dice roll -10 to +10, add score minus difficulty, stats again 1-10. This seemed ok on paper, but in play of course you quickly see that the dice is AS important as the stat, and randomness is the king, so I realized I had not found the answer, not yet.

Currently, I am waiting to playtest the following: Skill minus difficulty plus a dice rolling from -5 to +5, and you re-roll on 5s. This naturally has a curve, but simulations show that you often get results near your stat level, but can rarely get very very high and very very low results, which seems desirable, as it maintains the importance of stat over random die results. One of the key problems I'm facing is that the dice must roll -5 to 0 to +5, because if you cannot roll 0 on a re-roll, you cannot get 5 (and wow, I just had a neat idea.. but I press on)

The problems I'm trying to figure out are:

1. How can I make a die where you can roll -5 to +5 with 0 (11 .. )

2. With 4.0's table, it was a cinch to calculate damage based on your roll result (1-10), whereas now it requires some multiplication. Ideally I'd like to be able to say a weapon did 0-68 damage and get that result quickly from a result of 1-10 on the dice

3. 4.0's table also allowed a quick injury calculation, where if you had 40 body, a hit of 14 was quick to see as a 4 (3.5) but now it requires a division, or a mini-table.

Any questions, or suggestions most welcome!