First, for the account expiration problem, check that you have set managed account lifetime minimum 30 days in GPO and that setting has been applied.
For x86 problem, maybe I would test first on few x64 machines that x64 client really works and forget about x86 at start. No one uses x86 anymore. Instead of installing MSI with GPO, you might want to look into GPO Preferences Task Scheduler, which is better software installation mechanizm I think. Maybe there you could add some script to recognize, which architect should be installed. GPO msi installation is more dummy solution, Task Scheduler would be better.