Yes msizap is "unsupported" if using the version lower than 3.1.4000.2726, also if you call it like this "MsiZap.exe GWT! {GUID}".. its not running the "a" option which would not change ACLs. That's why there is no option in the extension to allow parameter change. I've been running this for a long time on windows XP, 7, 8 and 8.1 and on 32-bit and 64-bit and have had no issues so far.
Use it at your own risk
Use it at your own risk
