nice

In first post or by clicking -> http://www.excessiveplus.net/files/forum/2009/12/quake_iii_config_editor_1.1.5_144.rar

every time i use this config I get an error where all the textures turn black
too bad, it was great for a noob like me

this is such an old post i dont believe the tool would even be suitable for the current version of the mod and widely used q3e executable.
My recommendation would be to make the changes yourself, either in notepad or directly ingame using /seta against each variable.

there are a few different options. probably best to create autoexec.cfg in your mods folder, then add the commands you wish to change there. most are generic and can be researched if you dont know what they do. some are exclusive to the mod, and some are exclusive to the executable.
to find out whats available you can either look through q3config.cfg or type ingame in the console things like /xp_ then press tab and it will list all the cvars
/cg_
/cl_
etcif there are settings you know you want but dont know the command, you can ask here on on the quake discord. https://discord.com/invite/bZp5Tuy
if you ask there we can help you create a config that suits you.
my direct discord superbad!#9105

there is a freon.cfg that can be loaded if you connect to that server/mod, it sets some basic settings but i dont recommend it due to a particular sound setting it changes. this wont be applicable if you're just playing standard excessiveplus.