Only becouse of your feedbacks, links and DIY instructions, I have done an upgade at X5 2003 with MKIV Navi, from ver 14 to ver 27.1 without any problems.
The improvements are significant - 3D option is an option is beter to have.
It's like moving from Windows to Mac, totaly new world

I have use Toastit software to burn CD and it accept all possible images without any problems.