The "FP" command will run a file from within a file - so if you wrote a file the has a popup to give you choices of files and set up variables to go to sections to run different files - something like this

'Make First Plunge... the following line will display first and wait for key stroke

MSGBOX(Is &ToolName tool number &tool in spindle? ,YesNoCancel,Change bit?)
if &msganswer = Cancel then ENDALL
if &msganswer = no then GoTo changebit

MSGBOX(Is Z axis zeroed? ,YesNoCancel,ZeroZ)
if &msganswer = Cancel then ENDALL
if &msganswer = YES then GoTo AlreadyZero

the MSGBOX sets up the question
msganswer is the variable
the GoTo sends you to a section of the file which in your case could be file names - then when you get there you run your FP command


hope this made sense

Tim