May I ask how the VirtualBox Additions WarpIN installer is going?
A few years ago, I buit a WapIN installer for VBox additions. It was easy to do, but totally useless.
There were two major problems:
1) You cannot get the files until after they are released. Meaning you need to watch for an update, extract the files, turn them into a WarpIN installer, within minutes of a new VBox being released.
2) Oracle has no interest in adding anything to their distribution of VBox, so users need to get the WaprIN installer from somewhere else.
A more minor problem, is that installing the addirions is not suited to using a WarpIN installer. It is better done with a REXX script. I have a REXX script that does part of the job (just do what the instructions say to do), but I haven't updated my script to handle the shared folder support.
I'd probably just use LIBPATH to get the VirtualBox drivers to be used instead of the preinstalled one, and I don't know how supported that actually is (seems to work on OS/2 Warp 4.52, at least).
That is okay, if you always make sure that the code is available, but if the CD (or image) gets unmounted, it could be trouble. Drivers don't follow LIBPATH anyway, so other things need to be done to get all of it done properly. Probably easier to just follow the instructions, and do it properly in the first place.
I also am unsure of when the libc stuff should be used or not.
LIBC should onlu be handled by RPM/YUM (use ANPM to simplify that). The LIBC stuff, that is in the additions, is usually out of date, and installing that can down level what is already installed. Remember that you are updating stuff in OS/2, not the host, and you need to use OS/2 tools to do it, using the additions (other than LIBC) from the VBox additions CD (or image).
Also remeber, that the OS/2 additions are not necessarilly updated at each VBox relese, even though the version might change. That doesn't really matter, you should still do the update, to be sure that you have the latest stuff.