"Yendorian Tales: Book I - Chapter I" - Hex-Edition
 

Hi. I finally found "Yendorian Tales: Book I - Chapter I" (thanks to Abandonia users :max:) and started playing it. However, as the characters upgrade to level 4, some sort of shareware protection does not allow me to continue playing.

After searching the web, I found some info on hex-edition: "Oh heck, I'll even be so generous as to tell you it's a single byte value located 28 bytes after the first character of the character's name. And if you still can't do it, I'll
write you a damned program to do it!"

I downloaded a free hex-editor and tried to modify the file "party.dat" in savegames folder, but it messed up the game.

Could someone please help me?

You'd need to know what to change that position, 28 bytes away from the first letter of character's name, to. I doubt simply changing that byte to something random will do any good.
What I can propose is - start a new game and save it into another slot/name, then compare that byte in question with what it is originally in your current savegame. Might be that it helps, might be that it doesn't. I hope you did make a backup of your savegame before editing it.

If you're successful, it would be a good idea to write down into a text file what the byte should be for the game to work past the shareware protection, for future reference and editing savegames. It's easy to forget.

However if you need help in Book I - Chapter II, that I can help with, to advance past a certain spot which marks the end of a shareware version. Depending on what shareware version of the game you'd be playing, of course. There is one with complete content of the full version, requiring a registration to get a password to advance, and a shareware-content-only version which strictly ends after reaching the end of the shareware point.