I have gone through 4 update installations to be finally able to know what fails and gather that information (1->reboot cycle-teeth gnashing, 2->white screen of death-head banging, 3->success, 4->document and check fixes)

I put this here in the hope it can help those of you who haven't still updated to avoid failure.
The first issue is the big update size. Make sure you have plenty of space before trying.
Second, you better make a backup of your system if you haven't done so (see this post http://www.internettablettalk.com/fo...8&postcount=31) and want to avoid a full reflash. Once you have a rootfs backup save the file in your PC to be able to reflash it with flasher, if things go wrong. If you have a bootable system in mmc, just do a tgz backup.

Now, lets start with all the issues I have found:

- The update can't be installed if sliderotate is installed. Simply uninstall sliderotate. Same with certain flash patch, it is documented in this thread (I do not have that patch)

- The update contains 32 deb archives. That in itself is not an issue, but, given how the package manager/apt works, means that if only one of such packages doesn't install, all packages will remain unconfigured leaving the system broken unless fixed by hand. So, for this very reason, use apt-get to install the update, and do not reboot if the update fails unless you have no other option.

- apt and the nokia repositories are updated too, if the update fails, the nokia repositories are borked and you won't be able to fix the system unless you already have all packages. Pre-download all packages first with "apt-get -d install osso-software-version-rx44"

- The update contains a documentation package. This package causes a lot of trouble, because it fails if the user has moved, removed or linked the documentation files:
It fails if there is no files in "/usr/share/pre-installed/MyDocs/.documents/". Create that directory and touch or put a file there if you have that deleted.
It fails if the "/home/user/MyDocs/.documents/osso_software_copyright.pdf" file is a symlink
It fails if the "/home/user/MyDocs/.documents/~sfil_li_folder_user_guides/" directory is a symlink or is empty. Make sure you have an actual directory with any file there.

- The init.d handling scripts are prone to fail, and because dpkg is not robust and/or post-install scripts have poor error recovery, causes the "dangling symlink /etc/rc2.d" problem. This problem doesn't affect everyone, and only happens on some packages. I think it is relate to how the post-install script passes arguments to the "invoke-rc.d" script, but I have to investigate further. In this update, the packages tablet-browser-daemon, mce, ke-recv and icd2 are affected by this problem and their installation will fail.
The best way to get rid of this problem once and forever is to edit the "/usr/sbin/invoke-rc.d" script and make sure it never fails the symlink check. There is already a thread about this in ITT. I have attached the fixed script here, so just copy it to /usr/sbin
A worse way to fix this is to delete the /etc/rc2.d related files (S99tablet-browser-daemon, S21mce, S30ke-recv, S59icd2) when the installation fails, then after successfully installing those packages (using "dpkg -i" because apt-get won't work) you'll have to create by hand those symlinks or otherwise the following things will not work right: usb, screen keyboard, network, power-off button. Those packages are tricky to get installed because they need other packages configured before installing, so you need to run "apt-get -y -f install" before "dpkg -i"

- Do not work through a ssh shell and don't let the tablet enter power-save mode. One of the packages is the network daemon (icd2) and will be shut down when installing, cutting off your shell. Since also mce is being reinstalled and has been shut down too, if you tablet enters power save mode you won't be able to regain control of it or even properly turn it off, leaving no other option than to remove the battery.

- It is possible to reboot with the update not configured if the only packages not installed are tablet-browser-daemon, mce, ke-recv, icd2 and the documentation, and then finish the installation by hand. Failure before that probably means endless reboot cycle.

- If the update has failed but you have been able to complete installation by hand, you have to "flash-and-reboot" to install the new kernel and initfs