BDV21EnhancementsOnly file

It's cool, take your time.

I figured it out. Load the enhancement mod first above any mod

How r u getting it to work? I tried it with the latest version of project brutality 3.0 github build and if I place the mod before pb3.0 it doesn't work while placing it after gives me script errors!
I am playing on delta touch by the way.

Nope still didn't work. Using the latest gzdoom dev build 4.5, the latest github build of project brutality 3.0 and placing your mod before or after project brutality 3.0 still gives me script errors.
As mentioned before I am playing on delta touch.

Well it seems that I am not the only one having the same problem.

It is technically playable for me if I load project brutality after the map enhancements but the issue is that project brutality nullifies 80 to 90% of the changes so there's hardly any reason to use the map enhancements at that point

To that regard, please make this zandronum compatible too.

I know about that. I actually meant for it to be compatible with mods based of zandronum.

I just released modified versions of Brutal Doom v20B and V21 myself and I learned this: gzdoom behaves differently depending on the order you load the mods in the command line (I have no idea how it behaves with mouse drag-and-drop, I'm using Linux these days...)
In order for my modified versions to work, they have to be loaded FIRST, and the Maps have to be loaded LAST.
Now, in this specific case you mention here, you could try loading the Map Enhancements LAST, this way I think you would ensure that its changes are kept there. Two conflicting sprites or textures might cause problems, I have no idea how gzdoom deals with that internally. gzdoom devs lazy as usual.

Well I had already tried your way {pb3.0 first then this mod last} and even though it worked the enemies all went missing and a ton of script errors started to appear. Like u I don't know how gzdoom works but hopefully a solution for this issue will be found soon.

All of this NONSENSE is gzdoom's fault... They could EASILY implement a function in the source code that "prioritizes changes made by the first loaded mod, and all following mods would be renamed". They already have a function that does this same exact purpose for Actor names, why can't they have for sprites too?
This is what they can do with their "20 years experience in C++ programming", the excellent "coders" LOL

Ever since gzdoom 4.4.2 things not only are going downhill but a lot problems are occurring that shouldn't be. From my experience gzdoom 4.3.3 was probably the best iteration of gzdoom there was. As a delta touch user I have been requesting the apps ownwr/author to bring it back as legacy sourceport but to no avail.... Yet!

The version of gzdoom that I recommend to always try first is gzdoom 2.4.0
Not only it looks the best but also it's compatible with most mods released out there.
After a lot of disappointment with newer versions of gzdoom, I found that the latest one (4.5.0 - october 2020) has reverted back to how the game looked back in 2.4.0, the graphics are bright, colorful and vivid once again. But there's one trick: you have to go into Display Options and use SOFTWARE Light Mode.
Another problem that's happening is that some stupid mod creators are using super-complicated and unnecessarily complex scripts for their mods, using new features that break compatibility with older versions. These new features of gzdoom don't really add any features that didn't exist since 2012 or some crap, they only serve to break compatibility. One example of this is the use of Nested Scripts. They don't bring anything that couldn't be done before, it only breaks compatibility. There were also a few functions that changed name (without the need for it at all) for example the well-known function A_CustomMissile is now called A_SpawnMissile or something like that. It is used in the Hocus Pocus Doom mod (that one is a perfect example of unnecessary new features being used without necessity and the mod could have been done in a much simpler way, requiring much less work to the mod creator)
So not only wrong things have been encouraged by the gzdoom team itself, also the mod creators have been doing wrong things. And we have to stop this tendency now before there's no change back. Alienating people is never cool. And requiring to have multiple versions of gzdoom in your disk is a lot of hassle, unnecessary hassle. gzdoom from 2017 (version 2.4.0) already has a tons of features that nobody ever uses, these updates and newer versions should be avoided when creating mods.
If you want to future-proof your mod for the future, and create less work for yourself, make it compatible with Zandronum 3.0. It is based in gzdoom version 1.9.1 (2016) and it has nearly all features one will ever need.
Have in mind that the game-changer mind-blowing mod Winter's Fury was released in 2006, long long before all of these newer stupid versions of gzdoom existed. All the functionality is there in the old versions, it's just fact. Pirate Doom too, it was released in 2013. After that period of time, gzdoom started to go downhill and the devs just becoming more and more insane.