Whilst a very good idea, I do have two points to raise with the execution of the idea. Please don't think I'm being overly critical
, the good points have already been raised in the above posts, and I'm simply trying to offer insight from years in software development and usability audits/testing:
1) Firstly, distribution method: why do you need an installer for this? Installers are simply bloat when you have nothing but an EXE. You're not modifying the registry (and if you are, why?) - it simply complicates things. It's not like you're trying to keep users out of doing any scripting manually, as you're requiring them (as you need to) to create/add to "init.sqf" to call your generated script. Additionally, if you absolutely have to provide an installer... at least provide an uninstall link in the start menu folder, too.
You might also want to consider either packing the installer into a single file, or making WinRAR extract silently. At first, I thought that you were simply using a WinRAR SFX archive to distribute the program (rather than just the installer). Also, the set-up files are not removed after the installer has run (which, given the above confusion, could be a bit annoying for users with less technical knowledge).
To combat this, you can cause an SFX to extract silently to the temporary directory (and clean up after itself) by putting this in the SFX's comment (the first line MUST be present):
;The comment below contains SFX script commands
Of course, this is largely a moot point, as there's little benefit to be gained from archiving an installer (as, if you've selected decent settings in your installer generator, it'll already be compressed in some way). It might be worth you reading up a little more on the Bootstrap installer for VB (which you've used) to see if it enables you to package an installer into a single EXE. If not, most archive software (e.g. WinZip, WinRAR, 7zip, etc.) will automatically extract a zip file's contents when a user opens a setup.exe (or install.exe) file from an archive.
As an aside: if you feel the need to compress your installation, I'd suggest you compress the application EXE itself with UPX
(or a similar solution), rather than use an SFX (which has a significant overhead).
Additionally, the uninstaller doesn't remove the start menu program group.
2) Secondly, what about clashes between variable names (either in other scripts, or simply through user-added tasks later on)? As you've used non-local variables (and rightly so), why don't you account for (or at least, drastically reduce the incidence of) naming conflicts by prefixing the variable names with your OFPEC tag
Overall, though, I think you've made a good start - it'll be good if you can tidy up the interface, and make the application handle the other aspects of briefings/tasks that were mentioned, in the future.