[2007 Micra replacing fan resistor]

I finally managed to get the connector off and the new resistor is in and I now have a proper 4 speed fan.

[2007 Micra replacing fan resistor]

The fan only currently operates with the switch on the highest setting.  I've watched the video for replacing the resistor and have successfully removed the glove box.  My problem is that I can't release the connector from the resistor body.  Is it safe to remove the resistor with the cable still attached and then disconnect?  Thanks for any tips on how to disconnect the cable as pressing the connector centre doesn't work, or I'm not pressing it right.