I've downloaded this game 6 times now, 1 manually, and the other 5 ones using the GOG Downloader.
This is seriously starting to melt my brain.
After each download, the chunks don't form an .exe file, and i can't install it.

I wait around 3 hours for each download to complete. And i don't have anything running in the background

If i remove the download from the list, and re-download the game, the integrity check stops at 476mb and skips to 1874 mb, again, not forming an .exe, everytime i redownload the game.
I have also tried to delete the files and download the entire game again, 3 times, with no avail.

I've checked the entire support section about these issues, but now i'm running out of solutions.
Someone help me, i just wanna freaking play Lands of Lore!

Have you contacted GOG's support?
Also LoL has its own forum here.

I can't help too much as I don't have Lands of Lore, but I distinctly remember someone else mentioning that the game won't properly download through the GOG downloader. Maybe try manually again?

Sorry, not much help.

Do make sure that you have some extra free hard drive space. I downloaded The Witcher 2 one day with the downloader, and it turned out it needed a couple of more gigs to put the downloaded files together. It wouldn't do it when I didn't have enough space, hell, it didn't even tell me that.

What is your OS?

Sounds like your downloader and browser are blocked from doing a disk write. What directory are you downloading to? If your OS is Vista / Win 7 then I would create a directory on C drive named "Downloads" making sure it was located on C and not inside your user directories or in the Program Files directory and point the DL there. UAC can sometimes interfere with disk writes to protected directories so creating a directory that is not monitored too closely by UAC may allow the download to be assembled when completed.

If your OS is Vista / Win 7 . . . did you install the GOG downloader as an admin? (right-click the setup.exe and click "Run as administrator" in the resulting dialog) If not, then you might want to un-install and re-install the downloader as an admin as you may have a partial install of the downloader.

As Pemptus mentioned you must have enough free HD space to write the exe file. I assume you have the free space but the disk write is still being blocked.

My firewall and AV programs have blocked disk writes on occasion. I have fixed the problem by making the blocked program exe a "trusted" program in the firewall (sometimes the AV program as well but not as often). I don't use the GOG downloader (I use Firefox) or I would tell you the name and location of the exe file to "trust". Look at the downloader shortcut properties for the name and location of the exe.

Usually it is my firewall (Comodo) that is doing the blocking so I would start by making the downloader exe a trusted program in your firewall. Also, if your firewall threw up an "Allow / Block" dialog and you clicked block then you may need to find the restriction rules and delete the block rule for the downloader in your firewall settings. If none of the above helps than you could temporarily disable UAC, your firewall and AV program during the DL but that would be ONLY as a last resort. That's all the suggestions I have . . . =)

It came out corrupted after 6 hours of downloading.

Happened to me at least a few times. But only once per download. A deletion of the files and a redownload fixed it quite nicely.

I like to be thorough. Never bring a rocket launcher to a napalm fight.

Try not using the GOG downloader and use the one that comes with your browser. I never had any problems with GOG games when I downloaded them via my browser.

Nevermind.
I fixed it after restarting my computer and re-combining the download (By removing it and re-adding it to the list)