Hi all,
first of all must admit I'm a spy in X5 world.
I don't own an X5 but a Z4 and as they share the Navi Software I am here to learn from you.

I recently updated my Z4 to V27 on my own, following your advice, as my dealer didn't want to do it. "No sir, we can't, new software isn't compatible, we don't have it..."
So, downloaded V27 and flashed on my own.
Now I would like to proceed to next step: V27.1 + Own Splash Screen (Boot Logo).

Here is where I get a bit stuck and I'm not that "hero" to try risking to get my Navi System fried.
I have created a new logo. It meets the specifications found in this forum.
I downloaded both GifExtractor and NavTweak.
I read all the posts I could using the Search function of this forum but still have some questions:
when I modifiy the Splash Image with GifExtractor, when I open the NAVBOOT file with NavTweak the Boot Logo and some other images get corrupted.

When I modifiy the Boot Logo with NavTweak, got no warning on image size (it's 12Kb) and GifExtractor can show them properly.

Now, my question is: Can I believe NavTweak and be sure the NAVBOOT file is still fine or do I really need to use GifExtractor to change the boot logo and try till it get's showed properly?

Thanks guys for your help,
Ka.