Hey, now after reading this post, I realize that we already were in contact by mail a few month ago, and you already made quite some valuable suggestions on how to improve R'n'D! I'm glad to see you here in the forum, too!
The ability to store all levels on the server PC, and have clients access the levels from the server.
This is in contrast with how it is now, which requires server and clients to have identical level files. Which makes it really hard to keep the networked game playing functional, especially if you are creating and updating levels as you go.
If I remember correctly, you already made this proposal for R'n'D in one of your mails, and I heavily agree that this is not only a very good idea, but in fact a more or less mandatory feature for usable network games in R'n'D!
Therefore, a feature that (hopefully) comes close to what you described is already implemented in that "leaked" version which you have tested (and which unfortunately did not work out of the box on your two machines for unknown reason).
The feature is implemented a bit differently from what you described above, as the levels are not stored at a central "server" PC, but still locally on this or that client PC (so not all clients connected via network can "see" all levels from all clients), but if you start a level installed on your client, it will get transferred to all other clients via the network server, so every client can play that level, even if it is not installed on that client, too.
Your suggestion would probably still be better (as all clients would then also be able to actively start all levels, regardless of where the level file itself is installed), but it would also add some more complexity (e.g. how to handle editing a "remote" level file locally in the level editor). But I like the idea of having simple access to all level sets from all clients!
Too bad that your two computers apparently cannot "see" each others using UDP broadcast! And I have no idea why -- I've tested this feature with my Windows 7 VM and (I think) also with my Windows 10 VM, and it worked fine in both directions, if I remember correctly (the Windows VM being either the network server or a network client, while the other network computer was a Linux PC.)
Hopefully I have the new feature of being able to directly enter the network server hostname or IP in the setup menu available soon, so you can test again.
I feel selfish asking for this without offering to help develop it, but as someone whose skills are strictly limited to VBA and SQL (and not very good at those, either) and with no networking programming experience, I don't feel able to help
Don't worry -- testing my new network code on your machines is indeed very helpful, especially as I do not have a native Windows system available for testing (but only Linux, Mac and Android, with Windows only running in virtual machines).
