[lch]

Now I understand what you are talking about, using two copies of the game and your own server - you are trying to set up a network game on a single computer, playing it locally, yes?

I am not surprised to see that this runs into problems. You should play a local game, not networked, if you want to play and host at the same time.

If you still want to do both on the same computer, then just to avoid strange things like those that you are experiencing, you should set the savepath's of server and client to be different directories when you start them up. Dominions uses these environmental variables when starting:

DOM3_DATA
DOM3_TEMP
DOM3_CONF
DOM3_SAVE
DOM3_MAPS
DOM3_LOCALMAPS
DOM3_MODS

You should use different values of DOM3_SAVE for your server and client, with a batch file / shell script for example. Using different directories for the game files doesn't do anything, as the save directory should depend on the user running the game, not the game installation. You can run with one installation, so long as you change the savepaths.