Hargle here from the total DOS collection group. Someone pointed out to me that there was some discussion going on and my ears started burning, so here I am. Let me see if i can answer some questions for you. Working in reverse order:
1. totalDOScollection.org is indeed our home, but our forum isn't really open to the public. If you really, really, really want to sign up and discuss helping the project out, then send me a PM here and introduce yourself. We're not trying to discriminate, honest, but we're also trying to only get people who are actually dedicated to helping the project out at this time. I don't spend much time on any of the forums- my time is better spent working directly on the archive and trying to check in as many files as possible.
2. nugnugnug.com/pc/master is obsolete. I can no longer log into that site to even delete it. Our new master lists and .dat files are available here:[You are not allowed to view links]
3. The .IMG files are definitely not Atari ST!
Assuming you're referring to these two files:
King's Quest [DC] (1984)(Sierra On-Line, Inc.) [Adventure].img.zip
King's Quest II- Romancing the Throne v1.1h [DC] (1985)(Sierra On-Line, Inc.) [Adventure].img.zip
(if not, these two are fine examples of how to work with img files)
Unzip into a temporary folder that is mounted for DOSBox
type "boot <file1.img> <file2.img>"
for KQ1, the game will start up and you can play directly.
for KQ2, the first disk will boot and ask you to insert the 2nd disk. Press Ctrl-F4 to switch between the two disks you mounted.
IMG files are kind of a special case in a DOS collection like TDC. Technically they aren't DOS games at all, they are "booters". Some booters have been converted to DOS by ripping the disk contents off and creating executable files from them. These games are tagged as [DC] in the zip filename and then the original disk .IMG files are relocated out of TDC in a separate archive. Games that have not yet been converted to running straight from DOS are tagged with [DC] in the filename, and then they have that weird extension of ".img.zip". These are placeholders that because of the tagging/filename can be quickly and easily searched for and located in the sea of files that TDC is turning into! [there's over 17,000 files now]
Someday (I have been known to convert games from floppy to DOS in my past) all of the ".img.zip" games will hopefully be converted and then those img files moved into a better home with all the other disk images we have accumulated.
That at least covers the question from the last 6 months anyway. If you have more, do please read the "intro.txt" which is at the root of all the TDC torrents. It explains a lot of our motives. I'll pop in here from time to time to check in on things, and do be on the lookout in mid Feb 2017 for TDC #13.