Script Wizard in Sql Express 2008 -- missing objects, blowing up

[Database Administrator]

I have a particular database in Sql Server Express 2008 that references some
tables on the same server in a different database. If I try to script it in
Sql Server Management Studio via "Tasks-Generate Script..." etc., selecting
all objects -- it would miss some of the objects in this same database (not
the other one). If I try to do it setting "Generate Script for Dependent
Objects" to false, then it won't script at all giving instead an "Object
reference not set to an instance of an object." error while performing
"Determining objects in database 'db_name_here' that will be scripted." task.

I wonder if anyone experienced something similar. I ended up creating a
Powershell script which I run against the same database successfully
scripting everything.

What's going on?