Hello! I was wondering if someone could take a look at my map to figure out why it's leaking. I've read through the Quake 1 Tool Tips and have tried replacing the broken brush, but it still leaks at the exact same spot, no matter how I change the brush.

The QRK for the map and QuArK's output files (.map, .bsp, .lit, etc.) and a tool log can be downloaded from here: https://ufile.io/togmlnky 

Sometimes it's not the leaky brush itself that's the problem, but the brushes surrounding it.

In this case, the brush that the pointfile travels through (the north wall in the nailgun room) looks fine. But there are a few brushes nearby that don't seem to be on-grid, notably the little octagonal recess housing the flame, as well as the cylinders in each corner. If you set your map grid to the lowest setting and zoom in on the vertices, or the points where the cylinders intersect the wall, they don't always line up:

https://ibb.co/7kFb5RM
https://ibb.co/jzwJ1Vf

This doesn't always break things on compile, but it can do. Assuming QuArk has some kind of vertex tool it might be worth tweaking them. Moving each cylinder so the center of the brush lines up with the corner of the room might help, too. 

As the title says, thank you for your response! Once I finish my homework, I will do the changes that you have suggested. One question that I thought of when I read your reply was that QuArK's grid can go below what I assume is 1 map unit, all the way down to .1 units. I was wondering if I should set my grid to .1 as you said ("...set your map grid to the lowest setting...") or to 1 unit. I'm not necessarily concerned about vanilla compatibility, so I'm assuming I should set it to .1 units? 

Apologies, I did not know QuArk's grid went down to .1 units. I would not go lower than 1 unit personally 

Actually I'll expand on that. Where possible, I personally would not go lower than 1 unit for anything structural (or even 2 units, since I spent many years in WC1.6a with that as the minimum grid). That's not to say you can't of course, but it can lead to various issues

I'm sure it would be fine going lower/off grid for detail brushes 

Thankk you! Using what you have said I will try to fix the leak! Once I finish my assignments it's off to the map! 

does anyone know if https://github.com/ericwa/ericw-tools is able to export a GLTF or FBX model, with the level textures and lightmap?