The script thing is minor - I doubt it even needs another script since it has 4 others assigned.
There is, however, a fairly major bug in that this Improved Crypt King hoses the memorised spells offset in a fairly major way. Look at bhcrypt.cre after installing BP (no other mods) in Near Infinity, and you'll see that offset (at 0x2b0) points to 0x768. Well,
NI can't even find that offset - after effects at 0x558, items start at 0x954 and the rest is lost in the void somewhere. It might be solvable by using more recent coding techniques in BP like SET_BG2_PROFICIENCY and ADD_MEMORIZED_SPELL (or possibly Nythrun's .cre ordering macros, but I'm not sure if even those would fix it). But there's less chance for error with those commands, and they're easier than the existing code anyhow.