Okay, first of all, there aren't any trainers or hex editors for Physicus. You don't even have a character in Physicus, much less any stats, skills, hit points, or
other traits you might conceivably want to edit. So there's not much cheat to be had in this game,
but if you need a puzzle solution or just want to learn more about this game, here are a few good links for you:
The Non-Boring Physicus Walkthrough, with detailed instructions of where to go next
at each point in the game to eliminate the tedium of excess travel, useless locations and time-wasting red herrings, but without spoiling any of the puzzles.
Physicus Review, with a spoiler-free overview of the game for those considering playing.
Universal Hints System is a great place to get a spoiler for one specific puzzle you're stuck on without accidentally ruining any of the rest of the game--they have
their walkthrough uniquely structured to reveal only one hint at a time.
The official homepage of the publisher, Tivola, is unfortunately in German only.
You can download a Physicus trailer here. The site is for Mac users, but the trailer (like the full game) works equally well on PC.
The rest of these links aren't related to Physicus, but you may enjoy them anyway... most of them were created by me or by friends of mine. (-: