You can:
- copy the whole package in the web app and change it, then use it
- do the same but locally
- ask package author to add some customizability if it makes sense
If you hit a file count limit, then you can either reduce file count/combine them, switch to the CLI, or pay for Typst Pro.
I had this problem with one of my biggest projects where I had a ton of code snippets, which is why I hit the 100 files limit. I just had to upload it to the web app to be able to easily share it and modify. I had around 300 files. So the conclusion is that free file size count limit didn’t change. Instead, I had to make it less convenient and put them all in a single YAML file and then access them by key.