At First, welcome to the Forum.
Hast thou already looked at 
3rdage.net? If thou speakest no german but english, that should be the first place for thee to look.
An other question first: Usest thou BFME 1 or 2? I'll explain it for BFME 1 but it should be similar with BFME 2
Otherwise, I'm sure there was a tutorial about this somewhere. But somehow I can't find it, so I'll try it on my own. 

Thy first point is something I actually do not know how to solve. So that's something where I can not help thee.
2. I haven't edited the spellbook for a while, so I'm not completly sure what to do. This should be explained by someone else.
3.To give thy Balrog the Ability to level up thou hast to add it to the experiencelevels.ini. If the Balrog shall level up like e.g. Saruman, search for Saruman and simply add MordorBalrog (that was the unitname wasn't it?) to the TargetNames row behind IsengardSaruman
ExperienceLevel	SarumanLevel1
	TargetNames					= IsengardSaruman MordorBalrog
	RequiredExperience				= 1	
	ExperienceAward					= SARUMAN_LVL1_EXP_AWARD
	Rank						= 1
	SelectionDecal
		Texture					= decal_hero_evil	
		Style					= SHADOW_ALPHA_DECAL
		OpacityMin				= 50%	
		OpacityMax				= 100%
		MinRadius				= 40
		MaxRadius				= 200
		MaxSelectedUnits			= 40
	End	
End	Then continue till Level 10.
4. I think it should be these lines
		UnpackTime              = 1800 
		PackTime                = 1600Just increase the number and it should last longer. But again I'm not completly sure about this.
However I hope this will help thee. 

sincerly Kolibri8
PS: Beest thou a native speaker or where art thou from?