Just wondering for when it comes time make my next run through the series. I might just make a TUTU install out of GOG's version if I know which, if any, patches have been installed.
Though it would be nice if GOG gave people the option of downloading a copy of BG1 already upgraded with TUTU just so the newbies don't have to deal with BG1's engine.

Normally, GoG includes the offical patches, iirc, but not the fan made ones. Could be wrong though.

Excellent idea! However, there are likely business relationship or licensing issues that might complicate this option for GOG to release various "flavors" of modded versions of their catalog (not to mention the additional workload). In addition to the potential business-wise issues, think about the sometimes contentious relationships between competitive modding communities supporting the same titles. GOG would wind up in midst of Mod Wars.
A potentially more practical solution using the new GOG platform and its expanded community features would be a repository and distribution sub-system for modding members "flavor packs." These could be QA'ed by the GOG community, rated, reviewed, etc. Then each product page could simply link to the community-contributed modded installs with a "use at your own risk" caveat. To really do this right, a GOG "modder's SDK" would be useful to generate documented and consistent user experience so that members could as easily grab and install a modded version as they do the de facto standard GOG release. Krypsyn, thanks for this clear and cogent statement of the basic requirements to do a Tutu mod of BG1. My primary interest was the potential for widescreen. A quick Google before doing a purchase resulted in a pile of conflicting opinion that stretch over a conversation taking place for what is now many years. I suspected what you clearly stated and so will be content with installing the GOG standard release and simply see what I can do non-invasive monitor setting-wise to adjust my playing experience. (Of course I will keep an eye and ear out here to see if my options change over time.) Thanks again for your insight.

Tutu (or Trilogy or whatever is most popular these days) is awesome, but just imagine the new life the series would get if Bioware just released the Infinity Engine source code!

I have tried Tutu with and without the widescreen mod. I actually prefer to put BG in the largest 4:3 window that my screen can support. The widescreen mod only applies to the tactical map (not sure what else to call it, the map where you move your party around and not the overland map). All other screens just show normally with black bars on the left and right of the screen. For what it does, it is very nice (the added viewing area on the map IS quite nifty), but it is far from necessary.

Edit:
It has been forever since I played Baldur's Gate in anything but the BG2 engine (via Tutu). I know the BG2 configuration tool allows for windowed mode, but I am uncertain if BG1 can be configured the same way. I just thought I would mention that, in case anyone is scratching their head about what I wrote.

I know Gabriel Knight 2 and Phantasmagoria use versions of fan patches to be able to run without CDs. The installer also includes the fan deinterlace patch for GK2. I think there are a few other games that do this as well.

True enough, I was thinking more of content modifications than specific mods used only to make the game run; I can't think of any content mods included in any GOG games. You are right though, there have been more than a few GOG games that have 'borrowed heavily' the no-cd crack from other sources. Personally, the whole pirating a pirate for a crack amuses me greatly.

My main concern is that BG1 is a VERY dated game these days without the upgrade to BGT/TUT or Ease of Use mods. Someone new to the series probably isn't going to be able to deal with the small item stack limit, or the very slow walking speed.
As for choosing between the two mods (BGT/BG1TUTU) a BGT install includes BG2, so they couldn't make a full installer for that unless they sold it as a separate pack, or had some check for people who had both.

I am not into gaming distribution business, so I'll just guess, but Hasbro is probably willing to have the game sold "as is", without any third party extension.

I have to say I've never played the first BG -it was very hard to find in Italy 'til now, so this is my first chance and one I'll make sure not to miss!!!- so I've never been able to try Tutu; however, somebody experienced with it may know its launcher and make us know if the cd is required by it or by a game check.
Our best bet remains to wait for the GOG version of BGII (which i hope is coming soon) and, eventually, make contact with Tutu devs to have it adapted.

It would also be nice to start collecting some infos on the most interesting mods online, and i'm sure to be almost naive by suggesting the Widescreen Mod.

It looks like the widescreen mod doesn't work with the GOG version, and according to [url=http://kotaku.com/5645570/lego-thor-is-here/gallery]http://kotaku.com/5645570/lego-thor-is-here/gallery[/ url]/ the maker isn't planning on making it compatible. Maybe a resourceful gogger could figure out a way to get it to work? The low resolution is kind of painful.

On a side note, the BG1 tweaks mod seems to work fine.

Okay that was obviously the wrong link, even though it's cool. The real link is http://forums.gibberlings3.net/index.php?showtop ic=21017

Ouch, i'm quite sorry; first of all, because of my error :) then because i'm going to play it in a virtual machine, so having it not on my native resolution means i'm going to play with some big black stripes surrounding the game area (unless i change the resolution of the host machine, quite boring...).

The problems does actually make sense because this is a kind of patch that is applied on the executable, and GOG has surely already modified it for other reasons (maybe compatibility), or at least "signed" it somehow; this means the patcher is not able to identify the executable it's going to alter.
The task looks well over my skills to me; i hope somebody's able to make contact with the mod creator and settle this somehow.

That's kinda worrying, and makes me wonder if tutu would work with a gog version of BG2, since I remember the last time I tried installing it I had issues due to having the wrong patched version.

I'm pretty sure that you can install Tutu and/or BGT with GOG BG1 and disk BG2; probably even with GOG BG2.