Hello, i have 2 beginner questions about HoMM3.

1) Does GOG complete version include all vids in the explansions ? I read online that some complete versions do not include those videos.

2) I have vague memory of 1 of the expansions from years ago when i played it somewhere but i cant seem to figure out which map or campaign it was looking at online videos and walkthroughs. What i remember is that when you started, there might have been a time limit, as in, how fast you need to kill someone or do something. And i remember this knight lady, must have been from Castle. And i remember seeing her army after i attacked her and she had like tons and tons and tons of units and i was like whaaaat, how am i supposed to win this and i quit. Catherine seems to be similar but looking online, i actualy play AS Catherine, not go against her. So maybe it was some other knight lady. It was probably first mission but i dont know which campaign of which expansion. All i know is that i played original HoMM3 campaign and this was so much harder than that that i was like, no way, to hard. Thinking of giving it a shot again since price is low, but i want to find out the name of the mission

1. hmm... intro's if im right. Instead of 3 there is only one.

1) What do you mean by "vids"? The opening videos, or the cutscenes with voiced text before campaign missions? When I start my copy, the Restoration of Erathia intro plays. Looking at the game files, I suspect the AB intro is there, though I don't have the codex or whatever to play it via VLC. A brief look online didn't yield any results for SoD even having an intro. The pre-mission cutscenes for each campaign mission are all present and play.

2) There are several timed missions, campaign and non-campaign. There are also a number of missions with huge enemy armies at the end to defeat. You'll need to provide more details to help narrow down the specific map.

If you about HD+ mod, it is not only resolution but some else tech and gameplay QoL improvments. If you ok with that - it is must have mod.
If you about Heroes(*3*)GL aka GL wrapper mod, it i again a bit more than just resolution mod. Also Verok's wrapper-mods make game always been windowed, that mean it take resolution from Desktop and few else... aspects. But if you want to play H3 in maximum 'clear' original state but +widescreen and very minimum tech\QoL - chose HeroesGL. If you need a bit more QoL (i alwasy think H3 have auto-resolve+manually, but looks like it always be a HD+ feature - clear game do not let you chose re-fight auto-battle) - HD+ mod. HD+ as it stated on of.site include render from GL (im personally didnt test it, just install H3 right now for few random maps and that all).

There is re-implementation engine port-mod for heroes3 (jsut liek other one for heroes2), you can find link here:
http://www.pcgamingwiki.com/wiki/Heroes_of_Might_and_Magic_III
This one even more QoL.

Heroes Chronicles supported only by HeroesGL. Only HeroesGL do not touch\dont care for any original files (well, port-mod too since it is opensource engine port, but that same as replace exe-dll files of original game).

As for 1.jpg screen, as Bookwyrm627 say, in-campaign videos are there 100%.
Almost all games miss some content or features during patches. Especially games with huge expansions. Some games with very-long life support like Wc3 did that few times. H3 Complete is H3 Complete, separate versions is separate versions. Remake is remake (HD(SD) Edition by Ubisoft).
Digital editions add more to that differences, especially when IP\publisher changed and new one bring what they found.

Some games\digital releases have unique loss case's, but there is no specific content issues in H3 Complete\+GOG, that for sure. All campaign maps and their video intros included. Maybe localised versions have issues in Complete (PL retail, there if fix for it).
Mmm... or it did. For intros. Bookwyrm and that thread you found already provide info and links. As they all said - anyelse wasn't missing.

You can try to find English Heroes Chronicles as campaigns files for H3 Complete (decade+ ago it be more easy to find). But you miss video sequences in that case.

Also, GOG make a good 8in1 release of Heroes Chronicles, but then split it. If you buy Chronicles on GOG you still able to download original 8in1 release:
http://www.gog.com/downloads/heroes_chronicles_all_chapters/en1installer0

Based on your attachment, we're talking about the single intro movie that plays when the game starts, before you go to the main menu.

I don't think the AB intro video/movie is present in the GOG install game files (there never was a SoD intro video). If you look at the attachment, I've selected the two VID files I see in my installed copy of the game (which is the base GOG install).

VIDEO.VID is the intro video for RoE, and it plays each time the game is started. I tried making a copy of H3ab_ahd.vid and renaming it; the RoE video stopped playing (starting the game dropped me straight to the main menu; no intro video at all) and a flickering torch 'video' appeared in the corner of the main menu screen. Also, as you can see, the file size isn't comparable to the RoE video.

However, even if the AB intro video were present, all you could really do is swap which one plays when the game starts. If you want to see the AB intro, here's a youtube link: https://www.youtube.com/watch?v=Df1Xg6yEinc

I admit to some curiosity about why this aspect is important to you, since only one intro video can be played when the game starts. I'm not sure even the originally produced version of HoMM3 Complete included both videos; that would be something for you to ask Google. Fair enough. If you do run across it again, I'd be curious to hear which scenario (whether stand-alone or campaign) it was. That's a personal preference question. I'm running a 1366x768 screen resolution, and I'm fine with how it displays, even with the two black boxes flanking the actual game visual. Other people have bigger monitors and want more of it used, etc.

If its only the intro movie it doesn't bother me. I can play it on youtube. I was just afraid i was missing some important part by playing GOG complete version as opposed to first playing vanilla, then vanilla with 1 expansion then vanilla with the other expansion.

I like to keep each campaign as it was originaly designed to play. I can give you an example. Age of mythology. I never play gold version because it breaks the vanilla campaign. It adds some new stuff that original campaign wasnt designed to have and it seems to alter AI and things are just different, like different number of enemies appear at certain spots, etc.