Hi Antony,
You're not the first one to ask for the new sources. I myself have insisted that Locopon put the sources for the new DSL on snowcovered. However, if you look through the threads in this forum, you will notice that we are preparing a new release of DSL that addresses a number of unhandeled issues.
I have indicated a few sections in the source that need re-writing to function properly with DNN 5 and sent that to him. Locopon would include some new features of his own. This release is expected soon now, but I don't want to pressure Locopon: he better takes his time and come up with better code.
I would expect, if Locopon decides to put the adapted sources for DNN 5 on sale, he will wait until the final release of DSL. I do not know whether there will be a beta-release first (I would expect so, but this is of course up to Locopon).
After the final (stable) release of DSL (which I labeled DSL 3.0.6 - see what Locopon makes of it) I will once more remind him to upload the sources to snowovered. Thanks for asking. The more people that ask here, the better the chance he will do so.