1) No.

2) No. Not possible to change the the graphics of an existing unit.  No polymorphing or shapeshifting possible atm.

3) 2 is the only thing that will work for what you are trying to do.  You can't both activate the ability and make a melee attack during the same combat round.

You also don't need this line:

<PreventStackingWith>WaspStance</PreventStackingWith>

Setting <CanStack> to 0 is enough.

Also remove <IsForFormattedDescription> from your GameModifiers.  You have no formatted description, nor do you need one, because you are not using any variables in this spell.

Thanks HF works perfectly and mqpiffle for cleaning my code a bit, I thought <IsForFormattedDescription> was for the combat text that appears but I realized it is not needed now. The monk is not supposed to attack it has a built in counter-attack no matter what weapon it is using (will be using staff only once i get question 1 done.) The Styles are there to boost the counter-attacks.

And some more

4) The prophet realizing his own potential is supposed to gain extra level-ups at certain intervals every 5 level or so. So I thought about setting the units level one level higher when a trait is unlocked and picked at at say level 10, with this, borrowed from Paragon, however it doesn't seem to work as planned perhaps there is no UnitLevelUp and only a TargetUnitLevelUp?

        <GameModifier>
            <ModType>Unit</ModType>
            <Attribute>UnitLevelUp</Attribute>
        </GameModifier>

5) The Bounty Hunter gains extra gold from combat, by using the:           

            <StrVal>UnitStat_GoldFromCombat</StrVal>
            <Value>2</Value>

Which I assume increases the gold gain with +100% since the default value is 1?

6) I tried to do something similar to the mana/heal from kill with the gold but have not been able to find and gold from kill UnitStat. Is it somehow possible to add more UnitStats? Or are they part of the game engine code?

7) I also made a Pinning Shot ability for the Archer which is basicly the same as hobble only that it decreases the move by 2, I figured that SD might have picked 1 because they didn't want move to ever become negative. In general is there any problem with values becoming negativ? Would a negative attack value heal the target for example?

4) Doesn't work as of now, what I can figure out.

5) Doesn't work either I think, like you said, put the value to 100 but still only got 3 gold after combat with butcher.

6) What type of new unitstats is it possible to add? Only things that defines units such as demon and so on or other things that makes for more interesting abilities?

7) I see thanks, I'll have to think about something to do with that then. Since I also wanted to add some sort of bear trap ability to the ranger.

6) You can use them in a few different ways. The first way is to provide new attack and defense values. For example Stormworld has Arcane attack, which is defended by Spell Resist. The second way is to use it as markers, like I do, for a "demon" or something. This allows you to do special things to those marked with that unitstat, from abilities and spells ("spell deals X extra damage if target is demon"). You can also use unitstats as a way to unlock spells, or limit what traits units gain at level-up (ie "Unit must have at least 10 charisma or will not have option of Bard Path"). For an example of a bit more complex use: The Earthshakers: http://stormworld.wikidot.com/reliquary#Earthshakers which give you +1 unitstat every time you are hit, and when you have 5 or more you can use 5 to cast Shockwave.

8) Unfortunately I cannot allow it, it was licensed only for Stormworld. Purchased here http://www.turbosquid.com/3d-models/3ds-max-human-skeleton/599775

So that's what <UpdateDurationAtTurnStart> does.

6) They intentionally expire at end of combat. It would be no problem to keep the unitstats after combat, just remove the <Duration>.

9) You cannot place items in a unit's inventory or equip items with spells.

10) I see no reason this shouldn't work.  For testing purposes I would unhide the UnitStat and make it so it shows up in the unit details screen so you can visually verify whether it's working or not.  Just make an xml file and add this code to it:

<UnitStatType InternalName="UnitStat_MaxCounterAttack">
        <Hidden>0</Hidden>
        <UnitStatGrouping>UnitDetailsCombatStat</UnitStatGrouping>
    </UnitStatType>

11)Lifesteal spells are a special beast that I haven't really tinkered with yet. I looks like you can only heal the caster and damage the target in a 1:1 ratio.