I don't have a plus but I believe I have read that you can use a (WDLXTV) EXT3-Boot [non-flash] version of 1.02.21 on your live+ and get the advantages of the WDTVExt features on the plus. DO NOT try and flash with this version, use the EXT3-Boot only.
Windows 7 Ultimate with SP1
1.02.21 WDLXTV 0.5.1.4 (Beta)
Linksys - WUSB600N USB Adapter
DLink - Dir-655 Router
Atheros - AR8131 PCI-E Gigabit Ethernet Controller (NDIS 6.20)XBMC - The Future of Television