Just because your getting gas upto the injectors and the injectors are pulsing, without checking the differential pressures across the vapouriser you can't tell what pressure is there.
Once you've confirmed you have decent LPG pressure in the system, get the LPG mode scanned for codes, the Connect has a seperate 16 pin data link connector.
The solenoid fitted inline with the LPG feed pipe into the Vapouriser is prone to sticking and causing this sort of concern.
After you've opened up the gas lines though, be sure to carry out a leak test........
