migration problem

Hello
so i have wow cata 4.3.4 and i want to upgrade it to 5.0.4 or 5.0.1 what ever works
but i can't do that due to battlenet which starts every time i launch ''World of Warcraft Migration Setup.exe'' so battlenet deletes all files and starts downloading wod directly
i wonder if there is any possibility to migrate wow cata to 5.0.4 without the annoying battlenet application
i have all the migration files (approx 5gb) i have them in TempMig5.0/5.0Migration-data
and also this file Temp/5.0Migration/Installer Tome 1.MPQ
ps:i don't want to redownload the whole game it would take like 11 hours

In order to play in our MoP realms you will need 5.4.2.
One possibility is to overwrite all these files into your current 4.3.4. folder.

Thank you for your help.
But anyway i downloaded expansion3.mpq and expansion4.mpq (approx 3gb) from a post in this forum and it is downloading missing files (sound and some texture files ) in the background. However, the game works fine.