There is a lot to clarify
Templates:
Not very many templates add Hit Dice, so all that would do is increase your Challenge Rating and Effective Character Level.
Monster Class:
Only your levels with Hit Dice would count as a Character Level. Levels with no Hit Dice is "buying off your level adjustment" and only increase your Effective Character Level.
Examples of Effective Character Level vs. Character Level:
- 5 Hit Die Monster with +5 Level Adjustment and 5 levels of Barbarian
= Effective Character Level 15 (5 levels of monster + 5 level adjustment + 5 levels of barbarian).
- 5 Hit Die Monster with +5 Level Adjustment and 5 levels of Barbarian
= Character Level 10 (5 levels of monster + 5 levels of barbarian).
Divine Power:
Your Base Attack Bonus would be determined by how many hit dice you have from your combination of Template + Racial Hit Dice + Character Class.
If you are a Half-Vampire Minotaur with 8 levels of cleric, you would have 6 racial hit dice, and 8 levels of cleric. Your BAB would be +14 rather than +12.
Shivering Touch:
The controversy surrounding Shviering Touch, is the duration, and the high amount of ability damage with no saving throw.
Duration:
Does the spell allow you to keep dealing that damage 1 round per level? Does the spell automatically deal damage 1 round per level? Does the damage only last 1 round per level?
The way it is written (albeit poorly) it seems to allow you to keep making your touch attacks dealing 3d6 dexterity damage. Without allowing a saving throw, like other damaging spells so allow, that is rather very powerful for a 3rd level spell. DM's should either allow a saving throw or start introducing Cold Resistance/Immunities to prevent abuse.
Why is it so powerful? Without a way to resist cold or ability damage, you could very very quickly render people paralyzed (Dexterity: 0).
The way it was probably intended was as a penalty that lasts for the rounds indicated, similar to Ray of Enfeeblement - since that penalty doesn't allow a saving throw either. It is possibly, also, campaign specific. Since it came out in the Frostburn book, and many creatures have high cold resistance and cold immunity, it could mitigate possible abuse. There were ways to ensure that creatures even immune to cold would still take cold damage, but that implies a class or feat investment.
Metamagic feats, such as maximize spell, causing an unmitigated 18 points of dexterity damage could become very game hindering.
Touch Attacks:
Some attacks disregard armor, including shields and natural armor. In these cases, the attacker makes a touch attack roll (either ranged or melee). When you are the target of a touch attack, your AC doesn’t include any armor bonus, shield bonus, or natural armor bonus. All other modifiers, such as your size modifier, Dexterity modifier, and deflection bonus (if any) apply normally.
Touch attacks, as an attack roll, would be allowed to be iterive, based upon your Base Attack Bonus. Perfect example of this, is a trip attack.
You can try to trip an opponent as an unarmed melee attack.
Make an unarmed melee touch attack against your target. This provokes an attack of opportunity from your target as normal for unarmed attacks.
Some weapons can be used to make trip attacks. In this case, you make a melee touch attack with the weapon instead of an unarmed melee touch attack, and you don’t provoke an attack of opportunity.
But not all touch attacks, such as spells, especially those as spells or spell-like abilities are allowed to be iterative, because the spell itself is a standard action (and most times the duration is instantaneous). Inflict Light Wounds is a perfect example.
Casting Time: 1 standard action
Range: Touch
Target: Creature touched
Conclusion:
Only touch attacks would allow Shivering Touch to take effect. If you have a means of channeling a spell through a weapon, such as a Spellsword, Duskblade, etc.; then you wouldn't be confined to touch attacks - or unarmed strikes.
Commentary:
As previously stated in this answer, the spell is written poorly and could be misconstrued very easily. The spell is simply flawed. I, as a DM, do not allow it. Your DM needs to modify it (if he has some sanity) to fit within parameters of other touch attack spells. A good model would be Chill Touch. Allowing one touch attack a round, for the number of rounds listed, and a Fortitude save for half damage, could balance the spell out a little more. As it is right now, a Maximized Empowered Shivering Touch (causing 27 Dexterity damage with no saving throw) will get DMG's thrown at you.