Hi there! Just joining this discussion from The Netherlands with exactly the same problems you mentioned in this discussion. Last month, my new 2014 IS300h was delivered, but in the first day the Navscreen failed. First I tried the update via Mylexus.eu and installed VC03101D. This was much better than the first releases, but I asked my Lexus dealer in the city of Breda for the newest version, and I got the VC03101F sent on a USB-stick.
I managed to install this version via the "complex" method, not via the menu-structure, but via the car-software menu (by turning on and off the lights while pressing the Menu-button). If you are interested, please PM me, so I can send you a copy of the 2 files on the stick! (163 MB)
The SatNav works perfect now, and I've got the feeling that the speed is higher than before. No errors until now!
Unfortunately, I still got the Error id=214 message when trying to log in with the login and password given on my account at Mylexus.eu. I am using an iPhone 6 with iOS 8.1.1. Bluetooth connection is OK, also with a Hotspot, but I can't get the special stuff working, like Streetview etc.
Any ideas?