Installed unofficial LMDE KDE 32-bit on a modern machine (triple-core, 2.1GHz CPU, 2 Gig RAM). Typing from it now.
Good news

is that everything seems to work now and installation of files during install took only 9 minutes.
I had to add "nomodeset" at the LIve install bootup on the "Linux Mint" option. I thought that you had included that in the past. Maybe with the new installer things changed? Perhaps I should have chosen another option to bootup.
After installation, first boot stalled at Plymouth; the dots kept highlighting. I rebooted with "nomodeset" and took out "splash quiet," and it worked. (After changing the password) I ran DDM. It took 18 minutes to install the recommended nvidia driver. Is it supposed to take that long? I was getting status bar messages like, "debconf: Unable to initialize frontend: Readline." Like I said, it worked, so I'm not sure if you want me to play with DDM more and report results on the DDM thread. I'd be glad to if you think it might help.
A minor point: In the Welcome application the headings "Community" and "Contribute" were cut off at about "Communi" and "Contribut." While I appreciate fonts that aren't painfully small (like I find on so many websites), all the headings (including the "Welcome" and "Device Driver Manager" ones) would probably look better if they were slightly smaller.
After turning off some of the pretty effects, performance still noticibly lags. I tried changing the compositing type from XRender to OpenGL (as I've done with good results on this machine with LMDE in the past), and got a black screen. When the desktop finally came back, there were a few error messages saying some effects were not able to be restarted. Effects remained with XRender. I'll try again and report back.