I have been able to partially set up hammer for Underhell, but with a few side effects.
This is how I first set it up, there is no .Fdg file so i had to use hl2's. And the build programs are the same as hl2's too.
However, when I started a new map the error "missing material editor wireframe" came up. The editors material files were missing, so I did this.
I tried to copy over the textures.vpk files from hl2 over to underhell, by both putting them in the main folder and adding the path in the gameinfo.txt
The red marker shows what was already in the .txt file before I edited it. And it doesn't seem to have any textures for hammer? (could be wrong)
So I was now able to create a map with hammer with and without problems.
So this is a map I made yesterday.
As you can see the combine_s appear as soldiers. The textures work correctly, however, any new entities such as Weapon_melee_axe will not appear in the list.
there is a bypass for this though as I have done, but they appear as obsolete. The entities work ingame. but I'm not able to edit the properties, for example, you can not
choose a skin for the soda can, and properties like Uh_spotbodies does not exist.
So I hope anyone has a solution to this as Underhell is one of my favorite games out there, thanks.