Version 3.12 of MUSHclient has now been released. This fixes a bug in version 3.11 where each line you sent to the MUD would be followed by a blank line.
You can view the release notes for version 3.12
You can download MUSHclient 3.12 now.
If there are any problems, please post messages to the Bug Reports, Suggestions, or General parts of this forum.