After posting this latest version, I got to thinking and realized the new option to load UDFs is not limited to just one function. In fact it is possible to use just about any command in kixtart from the command line now.

For example:

I created a simple UDFLibrary with just one UDF in it:
test.kix
Code:
 

function echo($output)

  $echo=$output

endfunction


Then using the syntax of kixstart.bat:
Code:

kixstart test -f:echo('Hello World')

would display: Hello World

But, there is nothing stopping me from typing in this too.
Code:

kixstart test -f:$=echo('Hello World') ? $ ? join(split($,'Hello'),'Goodbye')

would display: Hello World, Goodbye World


Obviously this is exceptionally prone to typos, so use with care. HTH.