hola, this ubuntu's boys
For installing Dude on linux: http://wiki.mikrotik.com/wiki/Dude_Linux_Installation
For starting Dude: "gksudo wine ~/.wine/drive_c/Program\ Files/Dude/dude.exe" I just added that on the wiki http://wiki.mikrotik.com/wiki/Dude_Linu ... e_on_Linux
You must choose "connect", select "remote" and "127.0.0.1" (loopback) for local login in the server (*real* "local" mode doesn't work under wine).
"Remote connection by default uses TCP port 2210 for regular mode, and TCP port 2211 for secure mode, so make sure these ports are not limited by a firewall. The ports may be changed in the server's Global Settings menu. The default username for connecting to a server is “admin” with no password. You can change this later." http://wiki.mikrotik.com/wiki/Dude_usag ... ng_Started
Althought the default Ubuntu's installation doesn't block those ports.
hope this solves your issues (took me a while to realize this and changing ownership to .wine just messed up my .drmc, so, don't do that
PD: tested on 8.04