The car's in limp mode, quite typical when the ECU thinks a regen is required in the DPF. Several solutions are available:
1) Reset the ECU completely. Programming remains but all codes and statuses cleared. You need a Nissan Consult-II device or workshop equivalent to do this. The people that remapped your ECU should have been able to do this.
2) Remove the ECU's DPF code entirely. This includes the check of the DPF sensors. I am not sure this is possible - I'm not sure that anyone's delved this far into the code.
3) Restore the ECU to its original state (if the ECU remap guys didn't save a copy of your ECU's program then you'll need Nissan to do this), refit a DPF, have a forced regen performed and then either:
a) leave the DPF in place and continue driving, or
b) remove the DPF and obtain a pair of sensor replacements from auggie (a user on this forum), or
c) have all of the DPF procedures removed from the ECU
Good luck with yours. Obviously resetting it is the cheapest alternative and it might fix the issue. A first attempt would be a manual reset that you could do yourself:
* Get everyone out of the car in case it explodes, minimum safe distance is about 5 metres.
* If you use the information in your trip meters, write it down. Have the radio's PIN handy if it uses one
* Open the bonnet, close the driver's door (do not lock it)
From here on, only ONE person should be anywhere near the vehicle for safety reasons. You might consider wearing padded armor, although most times this isn't necessary unless your car's been parked in Afghanistan for any length of time.
* Remove the battey negative lead
* Open the driver's door, sit in the seat and put your foot on the brake pedal for 5 seconds (keep the driver's door open in case you need to exit quickly)
* Get out of the vehicle, close the driver's door, put the negative lead back on
Try the car again. It may be fine now - what you've achieved is a complete power-down (and a drain of any residual power) of the ECU which should reset any "active" codes. The ECU will possibly remember the previous state (stored codes) but may check the system again before throwing the warning lights - and may not find anything.