When telescope is installing it copies your mce.ini into /etc/mce/mce.ini.telescope.bak and then modifies the mce.ini. When it is uninstalling, it copies backup copy back to /etc/mce/mce.ini.
Updating the packet effectively results in its uninstalling and then installing again and after it all your changes to mce.ini is lost

So, you can do one of:

• Remove telescope, apply your changes to mce.ini and then install it again. Telescope will use your 'good' mce.ini as backup and so will not destroy your changes after update.[/*]
• OR Apply your changes to both mce.ini and /etc/mce/mce.ini.telescope.bak. (or you can even just copy mce.ini to mce.ini.telescope.bak, but in this case builtin maemo's taskswitcher will not be ressurected when you uninstall telescope)[/*]