You can always try using the 1.4.5 patches from:
Index of /feeds/webos-patches/1.4.5/
No guarantee they'll work, but some might.
I was able to install the fullscreen browser and auto-hide icons in browser patches via Preware.
EDIT: Actually, I just added the above url as a custom feed in Preware and was able to install a couple more 1.4.5 patches successfully. Not sure why I didn't think of that sooner
EDIT 2: Ok, I was able to install the following 1.4.5 patches on 2.x
Browser
-Auto Hide All Icons After Page Load
-Fullscreen Mode Browser
-Hold Tap Context Menu
-URL Shorten in Browser
Camera
-Capture with Volume Keys
-Simple Shutter Sound Off
Google Maps
-Auto Enable and Disable GPS
-Start in Fullscreen
Misc
-PDF Redux
-Unthrottle Download Manager
-Reset Options on Power Button Hold
Phone
-Enable Dialpad Vibration