Yes, I have the exact same problem. I can download the bonus content but not the actual installer file.

Some game installers have disappeared for me as well. The site's going through some changes, so it's just a temporary bug that should be fixed soon.

Just purchased Two Worlds 2. Game download not showing as stated above by others.

As well as:
Torchlight
Outcast
Anachronox
Gabriel Knight: Sins of the Father
Divinity 2
Arma II
Jagged Alliance 2
Ultima 7
Empire Earth
Witcher I
Beyond Good and Evil
Baldur's Gate 2
Ice Wind Dale I
Baldur's Gate I
Arcanum
Broken Sword 2
Beneath the Steel Sky
Might & Magic 6-pack
Original War
Fallout
Freespace 2

For me, Jagged Alliance 2 and Alpha Centauri

Yeah, some games are missing the installers...

I have the same problem, these Games I purchased won''t show the Game-Downloadlinks:

- Moto Racer
- Moto Racer 2
- Another World: 20th Anniversary Edition
- Torchlight
- A New Beginning - Final Cut
- System Shock 2
- Giana Sisters: Twisted Dreams
- Outcast
- Deponia
- Messiah
- Lionheart: Legacy of the Crusader
- Giants: Citizen Kabuto
- Freespace + Expansion
- Lands of Lore 1+2
- Alan Wake
- Empire Earth
- Bayond Good and Evil
- Dungeon Keeper
- The Witcher: Enhanced Edition (I downloaded this game yesterday with no problems)
- Divine Divinity
- The Witcher 2: Assassins of Kings
- Fallout
- Fallout 2
- Planescape: Torment
- Beneath a Steel Sky

In addition to the games listed above:

Sanitarium
Neverwinter Nights Diamond
Arcanum
Broken Sword 1

Seems to me that it is a problem with about one third of the games on GOG right now:

Back to the Future
Beneath a Steel Sky
Deponia
Fahrenheit
King's Bounty
Unmechanical
Fallout
Giana Sister's
Lands of Lore 1+2
Might and Magic 6-pack
Alan Wake
Alan Wake's American Nightmare
Alone in the Dark 1-3
A New Beginning
Alpha Centauri
Anomaly Warzone
Arcanum
Baldur's Gate
Baldur's Gate 2
The Ball
Botanicula
Broken Sword
Call to Power 2
Chronicles of Riddick
Constructor
Costume Quest
Divine Divinity
Divinty 2
Dungeon Keeper
Empire Earth
Enclave
Evil Genius
Fallout Tactics
Fez
Gabriel Knight 1
Icewind Dale
Icewind Dale II
The Incredible Machine
Jagged Allience 2
Journey to the Center of the Earth
The Longest Journey
Might and Magic 7
Might and Magic 8
Neverwinter Nights
Nox
Outcast
Overlord and Raising Hell
Perimeter
Pid
Planescape Torment
Puddle
Realms of the Haunting
Retro City Rampage
Sanitarium
Sensible World of Soccer 96/97
Stacking
Stronghold HD
System Shock 2
Tales of Monkey Island
Theme Hospital
Thief Gold
Thief 2
Tiny and Big
Torchlight
Trine
Ultima 7
Ultima 9
Undying
Wallace and Gromit
Witcher
Witcher 2

I'm seeing the issue with Fallout Tactics and Botanicula as well as others mentioned in this thread.

At least it should be fixed soon enough.

Lets see...

Torchlight
Puddle
Runaway 3
Deponia
Alan Wake
Divinity 2: Developer's Cut
Alan Wake American Nightmare
Chronicles of Riddick: Assault on Dark Athena
A New Beginning
The Witcher: Enhanced Edition
Baldur's Gate: The Original Sage
Baldur's Gate 2 Complete
Planescape: Torment
Neverwinter Nights: Diamond Edition
Icewind Dale Complete
Tower of Elemental Evil
Icewind Dale 2 Complete
Torin's Passage
Phantasmagoria
Call to Power 2
ZORK: Grand Inquisitor
Arcanum: Of Steamworks and Magick Obscura
ZORK Nemesis
Return to ZORK
Gabriel Knight: Sins of the Fathers
Syberia
Gabriel Knight 3
Empire Earth: Gold Edition
The Longest Journey
Lionheart: Legacy of the Crusader
MDK 2
MDK
Fallout
Fallout 2
Beneath a Steel Sky

Unless I missed some, that should be it.

Apologies for any repeats, and it may have changed since I went through my whole list, but here are the ones I noticed were missing just now out of my owned games:

Advent Rising
Alan Wake
Alan Wake's American Nightmare
Alone in the Dark 1+2+3
Anachronox
Another World: 20th Anniversary
Arcanum: Of Steamworks and Magick Obscura
Baldur's Gate 2 Complete
Baldur's Gate: The Original Saga
Beyond Divinity
Beyond Good and Evil
Blade of Darkness
Broken Sword 2: Remastered
Broken Sword: Director's Cut
Chronicles of Riddick: Assault on Dark Athena, The
Clive Barker's Undying
Deus Ex GOTY Edition
Divine Divinity
Divinity 2: Developer's Cut
Empire Earth: Gold Edition
Enclave
Fahrenheit
Fallout 1
Fallout 2
Fallout Tactics
Giana Sisters: Twisted Dreams
Giants: Citizen Kabuto
Icewind Dale 2 Complete
Icewind Dale Complete
Incredible Machine Mega Pack
Ishar Compilation
Journey to the Center of the Earth
King's Bounty: The Legend
Legacy of Kain: Soul Reaver
Lionheart: Legacy of the Crusader
Longest Journey
MDK
MDK 2
Messiah
Moto Racer
Moto Racer 2
Neverwinter Nights
A New Beginning
Nox
Outcast
Perimeter
Pid
Planescape Torment
Psychonauts
Rayman 2: The Great Escape
Rayman 3: Hoodlum Havoc
Realms of the Haunting
Retro City Rampage
Sacrifice
Sanitarium
Scratches Director's Cut
Serious Sam: The First Encounter
Serious Sam: The Second Encounter
Silver
Still Life
Syberia
Syberia 2
System Shock 2
Tex Murphy: Under a Killing Moon
Thief 2: The Metal Age
Thief 3: Deadly Shadows
Thief Gold
Tiny & Big: Grandpa's Leftovers
Torchlight
Two Worlds
Unmechanical
Vampire the Masquerade - Redemption
Warlords Battlecry 3
Witcher 2: Assassins of Kings, The
Witcher: Enhanced Edition, The

Good thing I keep backups for most of my games. What would I have done if I wanted to play one of these right now. :P I kid, I kid, of course. It's an odd bug, nonetheless.

I have the same problem, but rather than post another list (all of which may have been listed already :) ) I'll wait for a fix - or a first batch of fixes - and then go through what's left and see if I still have anything broken.