You should not calibrate your flaps in FSUIPC when using PMDG aircraft. As you have no profile-specific calibration section for your PMDG 777 )or the PMDG 737), the general calibration section will be used, where you have your flaps calibrated.
To prevent FSUIPC7 calibrating the flaps, with the PMDG 77 loaded, open the axis assignment panel, go the the calibration tab, and check the profile-specific checkbox. This will create a profile specific calibration section for this profile. Then go to the flaps calibration section and click Reset to remove the flaps calibration. You should also do this for the PMDG 737.
If your PMDG 777 flaps assignment to Flaps Set doesn’t work that well, you can try switching to use a preset. There is a preset available for this: PMDG B777 Flaps Lever Set
However, this looks to be for a potentiometer with axis values 0 – 1200. You can define your own preset (in your myevents.txt file – create this file if it doesn’t exist yet) based on that preset but for a standard axis range of -16384 to + 16384. i.e.
//PMDG/B777 300ER/Controls
My_PMDG_B777_Flaps_Lever_Set#@ 16384 + 327.68 / near 0 max 100 min sp0 l0 10 < if{ 507101 (>K:ROTOR_BRAKE) quit } l0 25 < if{ 507201 (>K:ROTOR_BRAKE) quit } l0 40 < if{ 507301 (>K:ROTOR_BRAKE) quit } l0 55 < if{ 507401 (>K:ROTOR_BRAKE) quit } l0 70 < if{ 507501 (>K:ROTOR_BRAKE) quit } l0 85 < if{ 507601 (>K:ROTOR_BRAKE) quit } 507701 (>K:ROTOR_BRAKE)Alternatively, you can assign to the presets that move the flaps between the discrete positions, using the PMDG B777 Flaps Lever n presets (where n is 1,5,15,20,25, 30 or Up – 7 discrete positions). You can do this on the right-hand side of the axes assignment panel, and leave the axis unassigned on the left hand side.