Welcome to the forum,

Either downgrade to v28 and backup to v29 or mod the revision number of the update, both ways are here if you search, however.

I use UltraIso, it will let you extract the navboot file from the v29.mds file and save back (the new image) to a v29.iso file (ready for cd burning)

Install UltraIso,
Then run UtraIso
File, Open "v29.mds"
Navigate to "V-2/RR/0101/BMWC01S/app_sw" in the now open image.
Drag and drop the navboot out of the image onto desktop (or sub-dir)
Open navtweak
File, Open "navboot"
Select the 2nd tab (images)

For sky select romicons #8 and right click replace, (with your choice)
For splash seletct rombitmaps #14 and right click replace, (with your choice)
For 3d icons rombitmaps select rombitmaps (you get the idea)

Then save the navboot (keep a copy of the original safe).

Then drag and drop into the open UltraIso session (back where you found it, "V-2/RR/0101/BMWC01S/app_sw").

The nav unit doesn't allow it to "update" with the same software as already installed.
So you have to fake the SoftwareVersion.
do the following: also extract the 2 .tbl files from the directoy:
<drive>:\V_2\RR\0101\BMWC01S
Open it in an HEX editor (like Freeware, PSPad http://www.pspad.com/en/)

In the first line you find: 30 39 31 30 This means: 0800 So: Software-Version 08.00
Just edit the last 30 to 31 and you nav unit will think it's a new Software Version and you can
update your V29 without prior downgrade to V28

The next time you update, you can edit it back to 0800 then 0801 again...

Save the UltraIso image as v29.iso, then burn a cd ad 1x speed.

Thats it.

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Sept 03, M3, Silver Grey. Retro-fits: Modded Mk4 DVD Drive, OEM Bluetooth, VR Control, Rainbow Speaker Upgrade, Sony SOT Amp, HK Sub, CCFL, Intravee II, NightMode.