It is not only possible to play versions 1.01 and 1.07 with Rune Classic, but also to host servers for these versions of the game.
To run a Rune 1.01 server from Rune Classic you need to:
1. Open Rune.ini located in your Rune Classic games System folder
2. Comment out the following lines by putting ‘ or // infront of them:
//ServerPackages=VWCreatures //ServerPackages=JunModel //ServerPackages=HallsOfValhalla
3. Rename JunModel.u to OldJunModel.u
4. Rename HallsOfValhalla.u to OldHallsOfValhalla.u
5. Start the server with the following command:
rune.exe DM-Hildir?Listen -VERS=101 -server
That is all! Now you can host a dedicated 1.01 server from you Rune Classic game and people who have normal Rune will be able to join your server! You do not even have to be connected to Steam when you start the server this way.
To run a Rune 1.07 server you would just change -VERS=101 to -VERS=107.