Adobe Sign - Changes Field Properties, how to fix?

Hello Everyone,

Thank you in advanced for any and all assistance.  I have an Adobe Acrobat Pro CS 5.5 Form that as several calculations.  They work and are marked as Read Only and Locked.  They are also limited to 2 decimal places.  The problems is when ever a client uses Adobe Sign with the form it modifies the balance due field, and adds 3 Extra decimal places.  Not sure why.  Not sure even how Adobe sign is doing this.

Example

Before Adobe Sign is used the Balance Due field will say 2611.70,  after Adobe Sign is used to get the form signed the Balance Due field will say 2611.70000.  Does anyone know how to correct this

Field Settings

General - Name BalanceDue, Tooltip Balance Due, Common Properties Form Field Visible, Read only, Locked

Format - Category Number, Decimal Places 2,

Calculate - Simplified Field Notation (Total) - (Deposit)

As a side not the Total Field equals 3070.9 and the Deposit Field = 459.20

Again Thank you for any assistance as I just don know how to fix this.