Lets start with, please be carefull, only use at your own risk. I tried and used everything I could think of to keep this virus/malware free, but you never know.

Hopefully we'll see the version of the .exe of the wallet increase when a new version arrives. Until then I'll use a different version for the installer (0.1.0 for this first one).
This installer will:
- Backup the %appdata%\BitcoinDark to %appdata%\BitcoinDark__, and reuse the wallet.dat and BitcoinDark.conf if present.
- Install the .exe in default location C:\Program Files\BitcoinDark or C:\Program Files (x86)\BitcoinDark on 64-bits systems. This is customizable in the wizard.
- Will install the %appdata%\BitcoinDark\BitcoinDark.conf (if not present), with the rpcuser and rpcpassword both with random 32char UIDs.
- Depending on the chosen settings, creates shortcuts in startmenu and/or desktop.
- Give a warning if the wallet is still running, you have to close the wallet, to continue. (Did not find a better solution yet)

Future installers will:
- Do the same as this one
- Uninstall older installations
- Prevent older installers to overwrite the newer versions that I made

Windows Installer version 0.1.0:
Download here
SHA-256: 733603F0680A53EE247C2B995A78D0F8B1930B4644A6564FF431C6F9384CA9E6

Have fun!
Qwitnix

PS. last test took over an hour to get connections, but in the end it got there, so be patient.

Edit:
Tested on:
Win8.1 64-bit
Win7 64-bit
Win7 32-bit