TILP is indeed an alternative to TI's computer <-> graphing calculator communication software. In a single program, it attempts to deal with the transfer functionality of the TI-GraphLink family for the oldest TI-Z80 models, TI-Connect for TI-Z80 and TI-68k models, TI-Connect CE for the TI-eZ80 series as you've seen, and the former TI-Nspire Computer Link Software ("TINCLS") for the Nspire series. It's open source (free software, even), and it works on Windows, macOS, Linux, and some BSDs.
TILP is the graphical interface which goes on top of the libti* libraries: libticonv, libtifiles, libticables, libticalcs. These which contain the bulk of the transfer functionality. Technically, TILP has a command-line interface, but it's pretty limited. And there's also the Group File Manager.
Although I've been less active for the past couple yars, and I haven't pushed out a release since way too long ago (but I've been providing build scripts for non-Windows, and pre-built binaries for Windows), I've been the maintainer of libti*/gfm/tilp ever since Romain Liévin retired in the summer of 2009. Most of the work is being done in
https://github.com/debrouxl/tilibs , TILP is in
https://github.com/debrouxl/tilp_and_gfm , and you can see for yourself the commit history, including contributions from other persons in the past nearly 15 years, including in 2023 and 2024
Indeed, there remain scarce online references about the hostile forks of the libti*/gfm/tilp stack, created by a former contributor to libti*/gfm/tilp.
AFAIK, there was never even a single release of the full stack of these forks.
A small number of interesting changes were contained in the commit history, among a large amount of noise largely caused by the churn of renaming mostly everything. I quickly integrated all but one of those useful changes, and the last one years later, when a larger number of MSVC users were using newer versions and could thereby rely on stdint.h (instead on removing it right away and making libti* impossible to build out of the box in practice for many users...). And that was that