The issue isn't that the items are bugged, it's that Ranged weapons are coded differently from other types of weapons. The Draw string will only appear on a weapon that has been given the ranged weapon classification (You can give any weapon model a bow string if you give it the right classification)
As for the animations / buggy sheathing that again is simply ranged weapons being designed differently from other weapons. Their animations are tied to the Ranged weapon classification and as such any ranged weapon model with a different classification will be considered melee weapons.
Your best course of action is to make your own custom bow/gun/crossbow using Epsilon's .forge item commands.
Also if you wish to use a ranged weapon and a melee weapon together you need to equip the melee weapon in the offhand slot then equip your ranged weapon. This will have your melee weapon sheathed while allowing you to unsheathe your ranged weapon for idle/spell animations. Just make sure to unequip your melee weapon before logging out as the game will delete the item when you log back in due to coding conflicts.
Another thing you could do if you want to be able to swap in and out of ranged and melee animations is to make /equipset macros
on your character window you can make equipment sets that will swap your armor/weapons when applied. These can be put into macros with spells and animation commands to allow your character to swap weapons smoothly while preforming animations.
macro example:
/equipset (bow)
.cast (Aimed shot spell #ID) Trig
Hope this helped in some way!