Apart from Blade Berserker, none of the other heroes have an inventory. As a result, the player character is unable to pick up tomes and other items to aid them in their journey.
All heroes should have an inventory, so they can pick up tomes and items.
you can fix this yourself by opening the map in the world editor, opening the object editor, adding the Inventory (Hero) to each hero’s Abilities - Normal list field and saving 
I can get into the editor and make the changes. However, it won’t save and would always throw up this error: Unable to open file: Maps/scenario/(4)warchasers.w3mTemp/war3map.j
Any ideas on how to solve it, so it saves properly?
idk at this second but I can peep it later
didn’t have any problem saving myself, here you go:
https://www.hiveworkshop.com/pastebin/f226f6cf9fdfe5a00262793195a3d228.29895
Thank you, that solved my problem. I can now play the fixed version via custom maps 
And US East servers while we’re at it?