Only KDD and JtRH. TCB and GatEB have more levels, but they vary in size and content and aren't strictly sequential. TSS isn't strictly sequential in more ways than one (hurr hurr), and it's truly huge with 43 levels and 888 rooms.

Yay, new friend!

So what you should do now is create a Caravel account, contact Support, enclose all your GOG receipts and ask about:
- adding your GOG games to your Caravel account;
- the bonus element pack which comes with TSS;
- free CaravelNet sub;
- playing the holds from 1, 2, 3 in the v5.1 engine;
- butterflies.

Are you trying to kill me? XD

I can import my savegames too, right?
Anyway, at this point for Drod1 I'll resist a bit more with the original engine. I'll switch to v5.1 if I get really stuck.
(but should I do the CaravelNet thing asap?)

Also, should I pass directly to TSS sequel when (if) I complete D1? Are Drod2,3 different enough?

Thanks again!

(Crap, I tried to make a joke and ate my own post. Serves me right.)

Probably yes. You should ask Caravel support how to do it (log into CaravelNet from your KDD game and wait for saves to sync?).

Not asap, whenever you like.

No no no, you should play 2 or 4 or both, then 3 after you win 2 and 5 after 3.

The storyline goes (4) - 1 - (4) - 2 - 3 - RPG - 5 - 5̘̣͕̬̠͐͐ͩ́ͅ ͇̖͖̾̅ͤ̅͜-̱͇̲͕͛̂̃̇ ̣̊͝5͈̮͇͍̠̠́͡ ̹͍͖̪-̥̪̩̀ͩ̓̉ ͏͚̝̺̠̜̻̰5̘̘̝̙̝̱̳̊́̐́͗͊̇̀̕͠ ̴̯ͮ̃͊̿ͬ̓͢͜-͔̺͇͈̞͕͗̉̌̿́͠ ̢̬̤̦͙͍͇̤̂͠ͅ5̤͔̫ͧ̑̏̈́̿̓̈̊

The campaigns for 1 (KDD), 2 (JtRH), 3 (TCB) and 5 (TSS) form a single storyline featuring Beethro, sequentially introducing new elements and increasing in difficulty.

GatEB, the campaign of 4, is meant to be a newbie-friendly introduction to the series. You're playing Gunthro, Beethro's grandfather (who's dead in the main story), in a flashback when Beethro is telling the story of Gunthro's adventures to his nephews at home after clearing King Dugan's Dungeon, between 1 and 2. It has most of the elements from 1, 2, 3, some new ones, and prettier graphics.

DROD RPG is set between 3 and 5; you're playing Tendry, a minor character from 3. It has different mechanics (monsters have hp, the character levels up) and its own engine. It's basically one huge exploration / optimization math puzzle.

TSS is the final and the most hardcore campaign. The engine is comes with, v5.1, has the most elements, the prettiest graphics, and the much-appreciated Unlimited Undo.

You're welcome.

I have bad news - according to this thread on Caravel forums, this method is no longer accepted since the beginning of 2016 due to many such requests and difficulty of handling them.

Instead, Caravel made an option to redeem both GOG and Steam keys for games purchased directly from them (picture attached). This system has one notable flaw - people who registered their GOG versions before the end of 2015 can get another GOG key. At this time, it is possible to redeem keys for DROD RPG, 4 and 5 (rest will be available later). Each game is listed separatedly, so I'm expecting splitting DROD 1+2+3 on GOG into separate products in the future.

You may repurchase DROD from Caravel if you want. Entering CaravelNet details into existing GOG installation will work fine.

Well damn. How do people go about playing their externally purchased earlier games in 5 now? Is it impossible without a repurchase on Caravel?

Oh and apropos of nothing, would you happen to know anything about the beta hold Entry Point?

Oh great, now that I see that level 16 is full of non-transparent Tar.
The devs should really automate the process...

EDIT: I've found some simple tar mods here :)
I doubt there's an unlimited continue mod, though..

Oh damn, it seems that the missing room number was the secret at level 11!
I didn't kill the 4 Tar drops in the lower left corner, so the game didn't mark the room as complete.
Please tell me that I don't need to replay all levels from 11 to 16..
What happens if I've missed 1 room? No good ending?

No, you don't. Nothing bad happens. Normally, when you win a campaign ("conquer the hold"), the game will show the actual number of secret rooms per hold level and how many of them you cleared. You'll be able to switch between levels, locate the secret rooms you've missed and clear them. (I missed quite a lot on my first run.) After you do that ("master the hold"), the master doors (the yellow-and-black striped barriers) open. There's only one of those in KDD, on the first level, and the ending is through there (there's only one ending, too).

(TSS the campaign works differently. It has two endings, an overworld map to go between locations in-character and time travel as an in-game mechanic, and if you mess up, a hole in spacetime swallows your computer. Or so I've heard.)

Phew!! Thanks Gog for that.
Ty Starmaker.

O_o

Brains.. monsters should never have them! =:O

Damn, I'm stuck at the secret room of level 23 (S1E1).
Do you have any hint about it? (or even a solution)

Remember: moving in the 4 cardinal directions creates an impassable obstacle. Moving diagonally doesn't.

Walk diagonally to the top, continue diagonally to the east, then walk south dropping plates in a straight line (thus forming a defensive barrier), hit the orb and step north to complete the cul-de-sac. Then herd goblins normally (they're stupid in large groups) while being super careful to not leave any stray plates. Mop up the stragglers and you're done.

I don't have a solution file but there's Pearls' full letsplay of KDD on youtube (part 65 @ 5:15 -- not posting a link because it's really a fun and not too difficult level teaching an important technique).

Phew, I made it, after like 100 tries +_+
I eventually used the suggested Pearls' solution, even if it has been still very difficult, due to the missing undos and some different behaviours (?).

I can't say I learned any technique here.. unless you're talking about the diagonal movement on trapdoors, which I've already used various levels before. It's the goblins army that makes a big difference. O_o'

Hopefully I won't get badly stuck again..

Doesn't matter if you kill them or let them live. They'll make more sense in the later games. KDD didn't really have a story at first. They added something to the Master level I think for JtRH. The tar guys were probably added as well. Plus, it's fun to hear them argue.