WebPlus X4: Form field read only conditional script

Does anyone know a script to utilize the read only option with form builder in X4? What I am looking to do is add a couple of fields that are read only until/unless another edit box field's value is 50 or greater.

I was looking into using a jquery hide/show, or javascript hidden script that would hide the fields unless the edit box field's value was 50 or greater...but I couldn't get that working either.

Thanks in advance!