Adding new units

Hello, i just want to ask something about adding new units to mtw. The problem is as follows: when i try to add a new string to the " crusader_unit_prod11 " it often gives an error message, like " invalid format, building laber should be " BUILDING_BUILDINGLABER ", despite the correct building laber is written. For example, building requirement " SPEARMAKER3 " is not allowed for unknown reason. But spearmaker level 3 exists in the campaign so i don't know what's wrong. Another error is simple, " uknown unit type at column Y and string X ).

Why it doesn't work, i don't know, since everything seems fine, building requirements, faction ID, and region ID for those units that you can only train in specific provinces.

Let me do a brief example: i try to make bulgarianarmouredpikemen recruitable but it gives me error, despite i modified the FN_FACTION ( BULGARIAN ), to HUNGARIAN, a faction that exists in vanilla mtw ( while bulgarian does not exist in vanilla )

I followed some guides, where they explain how to add new units, followed all the instructions and it still does not work. Since i want to add many new units to my personal modification, i'd appreciate very much some help from someone who can mod mtw, thx a lot.

Cheers