Okay I followed the conditional formatting you have for the table. However, anytime I enter in a number only 1 row appears no matter what the number is. I added the three rules you applied to your table: (field1 = Number and group2 = RepeatingTable)
Number is Blank = Hide this control
Expression: count(preceding-sibling::my:RepeatingTable) + 1 > ../../my:Number = Hide this control
Number is greater than or equal to 300 = hide this control
Any idea what might be causing this? I can attach a copy if you want.