I just went trough the procedure of horizontal MSX alignement, I did a rough calibration but I was more concerned about actually being able to tune the X offset rather than achieving perfect alignement right away.
I started by connecting my laptop to the E4 wifi broadcast and then using Putty to connect trough Telnet protocol (192.168.64.1, port 23).
To find out the current xpanVal of the camera, I entered rls .image.fusion.xpanVal
I was returned a value of 15, which I then changed to 10 by entering rset. image.fusion.xpanVal 10
The horizontal offset moved to the left, and was very close to perfect alignement. However the xpanVal gets reset when you take a picture or when the camera auto-calibrate, so it's kind of a pain to find the perfect value in a rush.
I then made a copy of my calib.rsc file from my backup folder and renamed it calib_old.rsc and edited the calib.rsc file to change the C1X value from 15.75798etc to 10. I deleted the last line of the file (# CRC32 2jvh2232etc) and saved the file. I installed 7-zip and with a right click on the recently changed calib.rsc file, choosing the CRC option from the window explorer menu, then CRC32 check and it gave me the new CRC32 for the file. Wrote the CRC down and then open the file and wrote it down at the end (# CRC32 etc). Saved the file and then connected to my E4 wifi again and using WINSPC FTP program, I connected to 192.168.64.1, username flir, password 3vlig trough FTP protocol. I went to the camera FlashFS/System/calib.rsc and made a new copy of it to my computer before replacing it with the new calib.rsc file. Then click disconnect, power down the camera, remove battery and power back up and voila.