Thank you, Mike, that worked. It took me hours of editing, but I finally have my tra and 2da files updated with the info about scrolls. I could use two 2da tables for this, but I thought it would be more sensible and easier to maintain to keep everything in a single table. In order to do this, though, I had to include the file extensions (spl or itm) in the 2da file, for otherwise there would be name conflicts. So I added some logic to my tp2 file to distinguish between scrolls and spells:

COPY - ~AlonsosMod/spells.2da~ ~AlonsosMod/spells.2da~
READ_2DA_ENTRIES_NOW ~r2en_spells~ 3
FOR (row = 0; row < r2en_spells; row += 1) BEGIN
    READ_2DA_ENTRY_FORMER ~r2en_spells~ row 0 resource
    READ_2DA_ENTRY_FORMER ~r2en_spells~ row 1 name
    READ_2DA_ENTRY_FORMER ~r2en_spells~ row 2 description
    
    INNER_ACTION BEGIN
        ACTION_IF (FILE_EXISTS_IN_GAME ~%resource%~) BEGIN
            COPY_EXISTING ~%resource%~ ~override~
            ACTION_IF (~%resource%~ STRING_CONTAINS_REGEXP ~spl~) BEGIN
                SAY NAME1 (AT name)
                SAY UNIDENTIFIED_DESC (AT description)
            END
            ACTION_IF (~%resource%~ STRING_CONTAINS_REGEXP ~itm~) BEGIN
                SAY NAME1 (AT name)
                SAY DESC (AT description)
            END
        BUT_ONLY
    END
END

WeiDU complained about that, though, so I must have broken some syntax rule there. Can you tell what the problem is?

Thanks, Mike, that fixed it.

And my mod is finished now! 

Who wants to be my guinea pig and try it in their computer?

That sounds good. Quick silly question: So far I've only tried the mod in BG2, right now I don't even have BG1 installed, so I guess I should publish it in the BG2 modding subforum of Beamdog rather than in the general modding subforum, right?

I intend to make it compatible with BG1 in the future, so I've published it in the General Modding subforum: Improved Spell Descriptions. So there goes my first mod. Thank you for all your help!

Thank you, Gwendolyne, that worked like a charm!
 
In order to streamline my workflow I modified a bit that routine to make it generate also the spell file name, apart from the spell name and the spell description. I attach the generated file to illustrate what I'm doing. My goal is to use just string references, rather than string literals, in my tp2 file. This is what I want to do:

COPY_EXISTING @100001 ~override~
SAY NAME1 @100002
SAY UNIDENTIFIED_DESC @100003

Here, @100001 would be something like SPWI201.spl. However, it looks like doing this breaks some syntax rule, WeiDU complains about that @100001 reference. I attach the debug file with the error. What am I doing wrong?

That sounds great, Gwendolyne. Take your time.

Thanks, that looks promising. So what would be the full contents of the tp2 file?

Yeeeeha! I have created my first mod! I'm the best!

At least in my computer it works. Would you like to check if it also works in yours?

Thank you, that worked. We're getting closer!

I have already edited thirteen spell descriptions, and I'm starting to realize that this is an awful lot of work. Eventually I'm gonna edit hundreds of descriptions, so I think it would save me a lot of time if I could export all those descriptions and their file names (SPIN943.spl and the like) to a big text file and work directly with that text file, instead of having to find and copy the spell descriptions and their file names one by one in NearInfinity. I have tried a couple of ideas in this sense, but none has helped:

- I tried the Mass export tool in NearInfinity, but it just exports a few thousand spl files in binary format. I guess the references to the dialog.tlk strings must be there somewhere, but I don't know how to find them (or even if they would be useful if I did).

- I had a look at the dialog.tlk file, and yes, the spell descriptions are there in plain text, which is nice. They are tangled in funny ways with other strings, but that shouldn't be a problem, I can untangle them. The problem is that I don't have a mapping of these descriptions to their file names (like SPIN943.spl), and without that mapping the descriptions are useless to me. I could still edit the dialog.tlk file directly, but you told me at the beginning of this thread that doing so is "frowned upon" because it is "destructive compatibility-wise", so that's a no-no.

So I'm wondering if there might be any way of exporting the text of the spell descriptions linked to their file names.

I have an awful lot of mod ideas. I have published the list here. As I say in that thread, many of them are not very suitable for a complete beginner, so I would like to start with one of the easiest ones. From the conversation in that thread it looks like some easy ones are:

- Combat log: Say when a character uses a wand or some other magical item.

- Fix Zone of Sweet Air.

- Improve the descriptions of some spells.

Looks like the last one would be the easiest one, I imagine it's just changing a piece of text.