Hello Guillaume,
Yes, we do still offer all of the Labwindows/CVI run-time engines free for download at our public website. From www.ni.com/support, choose "Drivers and Updates" under option 3, then "All Software Versions", then "Labwindows/CVI". I am including a link below for your convenience:
http://digital.ni.com/softlib.nsf/websearch/56E74D08EFDEFE2386256AE700639CB9?opendocument&node=132070_US
It sounds like you are already aware of how to exclude unnecessary run-time options during installation. A way to decrease the size of an executable in is to make sure when you build, to disable debugging. This will decrease the size of the file and speed up the execution.
I hope that this is helpful. Take care and have a great day!
Aaron B.
National Ins
truments