Basic Questions on modding pk3 (& other) Files (2.2.1)

[splat]

I was trying to mod the "0ufos.pk3" file and when I pack it in IZarc it packs to a different (smaller) size (even if I don't make any changes) and the program won't run. Is there a preferred zip program to do this?

Is there an easy way to increase the number of aliens on a map (Like double or more)? Also is there an easy way to make it cycle forever on the missions available so it's a constant brutal “bughunt?” I just want to splat aliens.

Otherwise, this is great!

[mattheus]

In moment - all teams - this means Phalanx, civilians and aliens - are limited to 8 actors. This is to be changed in future.

[BTAxis]

PK3s are zip files. Don't pack them as some other format.

[Destructavator]

If you're on Windows, the built-in compression in the explorer (right clicking on a folder and "send to compressed...") then renaming the extension from "zip" to "pk3" usually works in my experience.  There is also a .bat file included with the game, "archives.bat" that can re-build the pk3 files if you download the command-line version of 7zip - or at least the .bat file is included with 2.3, I don't recall off-hand if it's in 2.2.1 or not as it has been some time.

Zip files can be in more than one format, as far as I know the game can only work with one type of zipped files made into pk3s, so as BTAxis said, other types of zipped files won't work.

BTW, if you're testing changes, you can leave the folder un-zipped and the game should still find the files if everything is named properly.

On a side note, I actually played around with 2.2.1 .ufo files myself in the past and almost got a mod together, but didn't finish it, one that included researchable improved versions of weapons (including a multi-fire rocket launcher) and other stuff - I've been working on other stuff however so I never completed it, and I don't really know what you have planned, although the .ufo files alone can change quite a bit of the game.