Shaun suggested I start a new thread, so here it is.

There seems to be a differing opinion on whether this is a WAD or not:

Create a simple app (ie, it runs an MS patch: Qxxxxxxx.exe)
Set it to force run, but do NOT check "dist. always" and do not check
"run once".

User logs in, app runs, reboots, logs in again, and the app runs again,
reboots, repeat cycle.

Now, it was my understanding (which could be wrong) that the
application, when run successfully (to the extent that NAL thinks it ran
okay), writes the GUID in the registry.

Then, when you login again, it's supposed to check that GUID and if it's
there, and if it IS there, then it's NOT supposed to "run" the app again
(unless Dist. always is checked)?

Yes, I can workaround the endless reboot cycle one of two ways, but
neither way will let you reinstall the app if something goes wrong.

Workaround #1:
Set the checkbox to "run once". The problem with this (we had this
happen quite frequently with GroupWise) is that the app "runs" and NAL
writes the GUID and the app icon goes away. But during the actual
install, something goes wrong and the app does NOT install. User will
NEVER EVER get the app icon back to do an install again. User calls
helpdesk and complains. Now helpdesk has to manually find the app and
run it (in which case we have to put all the settings in that the app
needs as well as the settings in the NAL object so that it can be
manually launched via .exe or .bat or something).

Workaround #2:
Put a registry key check or possibly file check, etc. to see if the app
is installed. Again, problem is that if the app fails, that key or file
may already be written. So you can no longer do a Verify or Reinstall
of the app.

I have not yet tested this on an MSI-based app or a snapshot (that I can
remember anyway) to see if it has the same issues.