And more information.

Although I haven't checked it out, some posts I've read say that CDPR added the Witcher 2 modding kit to the Windows install. I'd have to install that version to check.

There is a DLC enable dialog available from the Options dialog in the Game Launcher that comes up first and from which you launch the game itself.

Most of the mods I've used so far are straight file additions or replacements. Like changing the image for the shoulder bag Geralt wears. As previously noted, some mods use the xml or csv files, and those seem to work fine. Depending on the contents, some dzip files work as well. This is probably limited to image replacement, xml, or csv files. I've changed the icons used for potions etc to the Witcher 3 versions. modWitcher3icons.dzip appears in my DLC enable list and works well although it's not really a big deal.

Having unpacked base_scripts.dzip to take a look, I decided to unpack a mod file to see what's there. I tried Dynamic HUD. I can put the dynamichud.dzip file into the CookedPC folder at the root level and it appears in the DLC Enable list. I unpacked the dzip and that results in two script files inside the folder structure where they would go. I tried the dzip file and also putting the two script files in the appropriate spot.

Dynamic HUD is supposed to hide most of the HUD until it's needed. So you don't see the things needed for combat until you're in combat. It's also supposed to stop the Minimap from rotating. Both tests, with the dzip file and the individual script files, stopped the Minimap from rotating. It also hid the other HUD elements. Unfortunately, it didn't bring them back during combat, making it a bit useless.

However, it does show that there's potential. For example, let's say a mod uses base_scripts.dzip but only changes one script. By unpacking the modded base_scripts.dzip file on Windows and identifying the changed script, you could copy that script file over to the Mac and put it in the appropriate location and it should work. Of course this assumes that the pre-mod script on Windows and the original Mac script were the same. Otherwise, other changes may occur or bugs may be re-introduced.

I do note that many of the mods that change base_scripts.dzip include the original file that they base the mod on. If I can find one with scripts that matche the Mac side, I may be able to unpack and use the modded script.

One of the dlc files was called abetterui.dzip. Opening that shows script files dated 2012. I'd have to install the Windows version to confirm that the same thing is in Windows, but it seems likely.

I'm going to do some additional tests but unless there's something I really need, I won't be going too much further. The one thing I'd like to have now is a non-rotating minimap.

I suspect any mod that changes base_scripts.dzip is going to be a no go. All of the scripts in base_scripts.dzip are .ws files and are straight text scripts. On the Mac, any scripts I found were .swf or flash files that need decoding to even read. I have not tried to see whether a .ws script does anything on the Mac.

Yes, I think you're right about the base_scripts.dzip being a no go and the .ws script is likely the culprit. That would explain why when it is added to the CookedPC folder the icon stays a blank white paper versus changing to a black screen with "exec" written in green on the upper left hand portion of the screen. For the record, once added to the CookedPC folder base_scripts.dzip does appear as an option to enable under the DLC option screen--only enabling it doesn't really do anything to the game.

I think I may do another post about all of the different file extensions for people who are interested in tweaking some of the existing files or putting together a whole new element for the game. For now though, my head is kind of exploding from translating and researching all of the different files I've come across the last few hours.

Side note, for anyone who's bummed about not being able to gain extra talents per level and wants a dirty work around, if you unpack the pack0.dzip you can get into an xml file called "geralt_skills." Here it defines all of Geralt's abilities in each of the talent trees. What the dirty work around would constitute is simply removing the second tier option from each ability and then rewriting the first tier's bonuses to include the second tier. I think once that's been completed I think you can just repack the file using the GRT Gibbed.Red.Pack function to turn your unpacked pack0 back into a pack0.dzip. Then you'd just replace your old pack0.dzip with your new one. It's not a perfect fix, but it'll get you something. I'll write a longer step-by-step later because right now my head hurts.

Additionally, there are two other Geralt related files called Geralt_basic and Geralt_levelups. The first seems to enable inherent skills like fist fighting and herb gathering, I think? The second deals with the bonuses from mutagens during Geralt's level up phase, I guess? I kept looking around both basic_scripts and pack0 for how talents were assigned and figured I could just change the number from 1 to 2 or 3, but never seemed to find it. Any comment on the contents of these files bobbd? Directions to the files (if you didn't already see them on your perusing): pack0/abilities/geralt_basic. The other two files (geralt_levelups and geralt_skills) are just right below it.

There's a list of file extensions and what they are at http://witcher.wikia.com/wiki/Extracting_The_Witcher_2_files. I have no idea whether it's complete or not and of course it Windows-centric so we'd need to find Mac equivalents to extract or unpack. I don't think I'd want to bounce over to Bootcamp every time I wanted to do something. That said, I wonder whether one of the emulators would work. Maybe Wine or something more powerful like Fusion or Parallels.

I'll take a look at those xml files. Lots of information inside. I wonder whether a modified one would have to be repacked. From my experience in other things, just putting the xml file in the right location should do it. For example, I installed the mod that makes Geralt look like Geralt from Witcher 3. It's a single file that's added in the appropriate folder within CookedPC. That file also appears in pack0.dzip, but the one I added takes precedence. I haven't checked any others but it's likely the same. If so, it would make simple changes a lot easier.

More research coming up :-)

Except for images and mods using only csv or xml files, this does not look promising. I took a close look at the Dynamic HUD mod. The part I really wanted was a fixed or non-rotating minimap. Unpacking the dynamic HUD dzip gave two script files, gui.swf and hud.swf. I compared both to their counterparts in abetterui.dzip, which is the improved UI from I believe the 3.2 patch. In any case, I couldn't find any differences, but there must be something.

I tried using the Dynamic HUD dzip but even if I disabled abetterui.dzip, nothing changed. I then copied over the actual swf files, gui.swf and hud.swf into the appropriate location in CookedPC. Those did make a differemce whether ot not abettui.dzip was enabled or not. Unfortunately, while the minimap didn't rotate, the part of the UI that was supposed to disappear in combat never appeared in or out of combat.

Out of curiousity, I tried using only gui.swf. Now the minimap did not rotate and the disappearing elements always showed. I checked the other things that abetterui.dzip was supposed to provide, and it seemed like everything was there. In playing for a few minutes I couldn't see anything missing or incorrect.

However, when I loaded an old save to check things out, I noticed that the minimap had north pointing down, whereas the main map had north pointing up. And while I liked the non-rotating minimap, having a different orientation from the main map made it annoying. So after all the testing, I'm back to what I had before.

The problem with substituting an swf file is that the original that it was based on may not be the same as what is in the original Mac game. So you don't know what else has changed.

It looks like unless someone makes a version based on the Mac original, we won't be able to implement script-based mods.

Just an FYI, it's a Virtual Programming eON port.

Just to be sure, are you using HASHING to compare the files?
Thanks!
P.S. Just in case, from terminal, for example:
md5 path/to/file1 path/to/file2