Yes, it's the same blockchain and address pool.
So it seems I could just send my Darkcoins from local wallet to a new Dash wallet, also on a local machine and that would be it?
...or, just rename the darkcoin data folder to dash, your darkcoin.conf to dash.conf and drop in the wallet.dat file from darkcoin in there and then load the new dash qt/daemon executable. It goes without saying to do this with the client/daemon closed.
Thanks. Funnily enough, my Darkcoin folder (that is in Program Files (x86) => Darkcoin does not contain darkcoin.conf. (not even peers.dat or wallet.dat both of which are in another folder, with Masternode data). I have no idea what I was doing, for I have darkcoin-qt.exe and a shortcut on desktop.
Now I dread touching anything
Your folder containing those files is hidden.
Since you are on windows, go to start and in the search box type "%appdata%" and click on roaming. You should see a darkcoin folder. Rename that to dash (again, when the wallet isn't running). Open up the newly renamed folder and rename your darkcoin.conf to dash.conf (you may or may not have one). Update any shortcuts as needed but the new default datadir is the dash folder that you just renamed your old datadir to (so no need to worry about redownloading the blockchain as it will be at the same height it was prechange).
Thank you for helping. I do not have darkcoin.conf in DarkCoin folder there (AppData => Roaming => DarkCoin) but it seem I can do what you say nevertheless?
Correct. Just rename the Darkcoin folder in roaming to Dash and run the new dash-qt.exe (it will know to look to the roaming/dash folder for your wallet.dat, peers.dat, etc).