We have a straight table in Horizontal mode which is behaving incorrectly. When using the IE Plugin you can see the output of straight table but in Ajax it appears blank. However, when you press the export to Excel button the data is actually there. There is no issue when the Horizontal is switched off.
Incidentally, the object has 10 Dimensions and 40 Expressions.
I have discovered that if you reduce the number expressions by 10 (doesn't matter which ones) it starts working again. I have raised this as a Case with Qlik to see whether they know anything about it.