No, Rudegar, you are wrong: the max. SD-capacity is 4 GB (non HC) SD cards, as I prooved with all working roms I tested, yet. (WM2k3 up to WM6.5 and I tried a lot of them!!)
Backpack is still available and some of its functions are working!
The vga-feature is working fine, after installing the driver.
Most ROM use additional battery in the backpack, but not all. You have to test yourself.
The only thing that won't work in roms, other then WM2k3(SE), is the compact flash slot, as there are no working drivers for WM5 and WM6.X (yet)!!!
The backup battery is changeable, you can use the one for the BA as they are the same. Use the search button above, you will find some links on this issue.
In case someone of you finds any mistake in spelling, punctuation or grammar in my posts - you can keep it !!!
Any language is Freeware - you can use it for FREE!
But, remember: They are not Open Source, you can't mutate, modify or falsify the Code, as you like to.