EvalAdd does not add in some cases

Hey again,

in my use case I have to add a value of roughly 400, so I noticed that the problem seems to occur for every scaleModSize.
For example for scaleModSize=58 it fails for values > 63 or for scaleModSize=55 a value > 512 can not be added.
I looked a bit further into it and e.g. for scaleModSize=50 it fails for values roughly > 16 000 (however, such big values should not be added probably).

So for me it seems that for every scaleModSize such a “threshold” value can be found.