HowToFix - FWF90DPOE - Policies/IPSec/Etc Stop Working w/ FortiOS 5.4.1

Hi everyone, I'm simply posting this in case someone else has similar issues with this model or some other people after installing 5.4.1.  After upgrading to 5.4.1 from 5.4 everything worked perfectly...until I had to power down the device and move to another location.  After moving it I noticed strange behavior, WAN to Internal policies stop functioning completely (not even a last accessed date on them), I couldn't ping from the FortiWifi to anything internal, my IPSec tunnel wouldn't come up, and my devices were unable to pull DHCP unless they had an IP reservation set.

If you come across this you will want to follow these steps:

1) Backup configuration.

2) Downgrade to 5.2.8.

3) Upgrade back to 5.4 (no higher).

4) Restore configuration.

I tried many variations of upgrades/downgrades and everything worked with 5.4.1 until you rebooted the device, factory reset and downgrade to 5.4 didn't help at that point.

Hopefully this helps anyone else that runs into this and saves them the hours it took me sorting it all out.