Moving a server from DMP to LMP

1. You need to have DMP and LMP installed. That's all.
2. Decide on whose progress are you going to keep. To keep it simple - in DMP every player has its own scenario and own progress, in LMP there is only ONE scenario that is SHARED across EVERYONE in the same server. Basically just pick someone with most science points/more developed tech tree and copy his progress. At this point, we are not really doing everything.
3. Now we have to save our universe from DMP server to local hard drive. To do this, we need to have running DMP server that we need to connect to. If we are connected, just click leave button in upper right corner and save locally. At this point we generated a new save called DarkMultiPlayer in our KSP installation folder. Now, we can turn off our DMP server and quit to main menu (BUT DO NOT REMOVE ITS DATA! We are going to use it in a while)
4. Okay, at this point our save is ready to be converted to LMP. Once you are disconnected from the server and in main menu, open up settings in LMP and choose "Generate Universe from saved game", after that you will be prompted with window called "Universe Converter" (it usually pops up in upper left corner of your screen) and you have to choose "DarkMultiPlayer" as universe that you want to convert. When you have any mods installed, click "Generate a server LMPModControl.xml" (3) and that will generate a whitelist of mods. YOUR FRIENDS/PLAYERS NEED TO HAVE THE SAME MODS AS YOU DO, OTHERWISE THEY MAY GET DISCONNECTED AND EXPERIENCE CRASHES OR NOT CONNECT AT ALL. Now, we successfully converted our DMP save to LMP's universe. Now - we need to set it up in our LMP server.
5. We are almost finished at this point! Now, enter your Kerbal Space Program installation folder and you should see a new folder called "Universe" and an .XML file called LMPModControl, if you see these - you did everything correct, good job! Now, we are going to put these files into our LMP server. Assuming that you already unpacked it (by "it" I mean server files) and put them somewhere safe (for LMP configuration please refer to LMP's wiki page) just straight up delete Universe folder in LMP's server folder! Yea! Do it like this! When you deleted it, just cut "Universe" folder and "LMPModControl.xml" from KSP folder and paste them into LMP server folder. Now - we ported our vessels and stuff but not SCIENCE POINTS and TECH TREE!
6. Grand finale. We are ALMOST done. One thing left - science and tech tree. Remember how I said that you can't delete DMP data and you have to pick the best player to transfer his progress? That's the moment that we use this knowledge. Navigate to your DMP server folder, and do as follows: Universe -> Scenarios -> [name of the player that you need to transfer progress from] and from this folder copy EVERYTHING (probably they are only .txt files)

Now navigate to your LMP server folder and paste it in: Universe -> Scenarios replacing all the LMP's files with these from DMP.

By this point - you finished. Now everyone has the same science points and tech tree as a player whose data you transferred, all the vessels should be in place and DMP was ported to LMP :)

Check it out by running your LMP server and connecting to it. Everything should be in its place.