I've found one on level4 with 3 exit stairs.
Which one should I take?

Can you also tell me how many secrets there are and in which level? (so I'll avoid missing them)

EDIT: found another at level5


P.S:
which are the savegames? Player.dat and drod2_0.dat ?

I don't remember how many secret rooms there were, but if you don't want to miss one, you shouldn't take any of these stairs and complete the level the normal way instead. When you take one of the stairs you will skip some levels.

Ah yeah, I found the info about the warp, so I didn't use it.
No lists about the hidden rooms though :|

Btw, some rooms are already quite hard :O

And they will still get much, much harder (and the secret rooms are among the hardes ones). ;)

Damn.. I wonder if I'll even be able to finish the game.
I wish there were more checkpoints\reloads, as it's easy to screw up some hard passages.

It took me years to finish the first game. I've started with the freeware version, took a long break because I had enormous problems with the slime levels (there's no timer in the freeware version) and started playing again when the game came to GOG.

But I really felt smart when I finally beat the game. :)

Reminds me that I still have to finish the second game (I'm stuck on level 24).

I knew that sooner or later I would have misclicked on New Game.. and that it wouldn't have had any confirmation.
Luckly there's a Restore option O_o'

If I remember correctly it doesn't matter.

And prepare yourself for a lot of evil tar levels. ;-)

Thanks and.. *shivers*.

I'm now at level 12, but:
- I've always found 1 secret room, except for level 1,2,9 (and 7 had 2). Did I miss something?
- on level 10 I found 2 blocked passages.
- after the start of level 11 I'm 1 room short and I don't know why.
- after the start of level 12 I'm 2 rooms short..?

Dunno, probably? Here's how many rooms total I see through CaravelNet, per level (I can't tell at a glance which of them are secret):
1 - 17
2 - 17
3 - 21
4 - 13
5 - 23
6 - 12
7 - 17
8 - 19
9 - 11
10 - 13
11 - 12
12 - 13
13 - 25 (troll level)
14 - 14
15 - 15
16 - 12
17 - 12
18 - 12
19 - 13
20 - 13
21 - 12 (best room is best)
22 - 13
23 - 13
24 - 14
25 - 12
coda - 40 (easy)

Oh yes. *Those* passages.

Dunno. I'd though it could've been because of a shortcut you didn't take, but 11 and 12 don't appear to contain shortcuts. Don't worry about missing stuff, you can always come back later. (I missed a lot of rooms the first time around, including both secrets at 7.)

Useful list, thanks!
I've missed only a room somewhere at level 1.
But why did it appear in the stats only at level11 room2 ? Hopefully it isn't a bug..

Uh oh, what do you mean, I'm in it right now.
It seems quite a maze :O

I've found an advice to just skip them for later.

-------

About your post here:

I only have 1+2+3, but they already seem enough challenge for me lol.
(unless they make a sequel with beatiful graphic and\or different game mechanics)
Also, paid subscription? Nooope
Too bad for undos.

What? No, it's damn opaque.

That's what I meant. It's an easy maze, too, it's just yooge. Blatant trolling has also fallen out of fashion (smaller, compact mazes are okay, though; Population Density 1 is what, four rooms?).

"For later." Hurr hurr.

They did. They're called DROD 2, 3, 4 and 5. Each adds moar mechanics and prettier graphics. Now 1 and 2 are shipped with the 3rd version of the engine, but 4 ships with v4 and 5 ships with v5.1. They're backward compatible, so the default holds of earlier games are playable in later games (although of course the campaigns themselves don't sprout new puzzles just because they're played in the new engine). But Tarstuff can be transparent and Undos can be unlimited (those are settings in the options menu).

You don't need to pay for the subscription, you only need to redeem the free months you get with the games to download the KDD, JtRH and TCB holds into DROD 5 (well, and redeem the games themselves, so you're allowed to download those particular holds). After you do, they're playable offline.
If you're ever stuck stuck stuck, about ready to uninstall DROD, etc, get Odd Jobs and Advanced Concepts. They're free.
(The free holds are just *.hold files and need no subscription whatsoever. There's a lot of free holds, but the best are typically the hardest; Odd Jobs and Advanced Concepts are newbie-friendly exceptions. Also, Entry Point, but it's in development.)

Open your damn PMs, I need to tell you something.

Well, the graphic seems slighly improved, expecially in TSS.
Do all the games have 25 levels? They seem a bit too long for such hard difficulty. O_o'

I keep them closed to avoid spammers and impersonators.
I sent you a friend request, if you want.