You could reinstall Blockland and activate the dedicated servers so they are made automatically.
Not sure if this can be done with the Steam version of Blockland (no way of testing)
Otherwise, your best bet is to make a dedicated.bat
Just create a txt file and write:
"C:\Program Files (x86)\Blockland\BlocklandLauncher.exe" -dedicated -map Custom
(or to wherever you installed Blockand, maybe an other drive)
Then change the [whatevername].txt to [whatevername].bat
To be able to do this, you need to be able see common extensions.
This is turned off by default on Windows 7 (not sure why as it can lead to security issues when it is off)
To turn it on, just change this setting:
http://windows.microsoft.com/en-us/windows/show-hide-file-name-extensions#show-hide-file-name-extensions=windows-7