PVX-I/O with Deltav SX controller inverting analog inputs

Does anyone know how to easily invert an analog input with PVX-I/O on a Deltav SX controller?  In Provox there was an invert option on the IST.  We have had to bring the input into a scaler function block to invert it and then to a pseudo AI custom composite block.  Also, in Provox you could make the 0-100% eng. units on an AI any direction and positive or negative.  We have vacuum readings that were scaled in Provox at 20 for 0% and 30 for 100%.  The top end of 30 is more vacuum.  These we had to change on the DV AI block to be -20 at 100% and -30 at 0%.  

Anyone else encounter these issues and find another way to work around them?  Thanks