"dpkg: status database area is locked by another process" is related to the aptitude package manager and lock files (think firefox on sunlab machines). The trick here is to open and then close the app manager application on the phone so it can clean up it's lock files. If that doesn't work. Restart the phone then open and close the app manager. If that still doesn't work you can manually delete the lock file, but this is somewhat dangerous.
To split images I would use cv::split(const MatND& mtx, vector<MatND>& mv). I would use imwrite to save the images and use the phones filebrowser to look at them. Interacting directly with the framebuffer on the phone is quite painful and requires a lot of knowledge of the stencil code. Make sure to check the documentation. For a lot of simple features opencv has functions similar to matlab to do things for you.
If you get the error: "/usr/local/bin/cs4670: error while loading shared libraries: libcv.so.2: cannot open shared object file: No such file or directory", try copying the .../HomeSetup/libs/ files into the Maemo libs.
Don't panic.