Your problem is still in Access. Did I mention I don't like Access? :)
The fields are not formatted right, and therefore when you run the data connection in InfoPath it does not handle them right either.
Open your table in design mode.
Click on the first weight field and see the format entry of fixed I put in. Also notice how when you view the data it shows 2 decimal places. In your form's data source, the weight field I fixed is a float, where all the others are ints, which only allow whole numbers. This is because the data in your table only shows whole numbers. If you enter data it just rounds it even though it is setup for decimals. This is what bugs me about Access, you have to specifically format.
You need to change the rest of the fields to fixed also. So that they all show the decimal places in Access.
Then rerun your data connection wizard and they will all be floats in InfoPath so you can configure the decimal format and they can handle decimal values.
I still think BC is going to need a SQL database for this and it would make your life simpler in many ways.
Have Fun