After or before installation you should put "codecs" to 
somewhere like "/usr/share/makedict/codecs". 
"codecs" is executable files except makedict in "src" subdirectory.

After that add "export MAKEDICT_PLUGIN_DIR=/usr/share/makedict/codecs"
somewhere into ~/.bashrc.

Examples of usage:
to convert from dictd format to stardict
makedict -o stardict file.index

to convert from dictd format to xdxf format
makedict -o xdxf path/to/file.index

to convert from dsl to stardict format
makedict -o stardict path/to/dictionary.dsl
