Ok, I'll bite
.
1. First of all, the model is in .mdx format with textures in .blp format. These are proprietary Blizzard/Warcraft formats that would need to be converted to something more readable like Autodesk .flc or animated .gif format. I would suspect that's possible given the converter info related
here but I don't have time to look into it further.
2. If it could be converted to a format like that, it can be converted to the
IE .bam format, but it's a lot of work (see
here for examples of porting from other games).
3. As for whether it could attack, cast spells, die, etc., that all depends on whether the original model has animations for all that.
4.
BG2 character models have overlays for different weapons and armour. Most likely, this one does not, meaning you probably have a hardcoded weapon and armour that can't be changed. Most liches anyway just use an undroppable "touch" type of attack with special properties, not normal weapons.
5. You need a paperdoll too, which could probably be converted from the concept art for the model. Like the models, this won't have overlays for specific weapons etc. without a lot of special work creating those weapon overlays etc. Likewise, it won't be paletted without a lot of extra work, meaning you can't change the display colours.