I played eschalon 2 about a year ago. maybe longer.

I still have it installed. I read about the fact that there is more content and I did not see an automatic update.

if I download it the version 1.05 with the game already installed will it need my code again? I am not sure I know where it is on my computer or if I wrote it down on paper.

You can download the newest version and install it and it will automatically find the registration. Installing the new version doesn't overwrite the preferences where it's stored.

sweet. now I am trying to remember all the cool stuff I have forgotten (like which abilities to buy at beginning of game and which to get books/training for)

played as a mage with no armor and played as a ranger. thinking of going ranger again.

does the new content just happen in game or is there a new area that is unlocked?

Some of the new content replaces old content, and one area that used to say "your destiny awaits elsewhere" now lets you go to a whole new fun dungeon.

Also, some new content is player mods not from the company itself. You'll have to read their directions to insert it into your game of Book I and II.

I haven't done the one for Book II yet.

Just for a change - have you ever played as a Rogue? It's a lot of fun....