Yes, I got problems to mount NFS to sdcard as well. I didn't find out the reason but I'm sure pcristi knows.
To get it persistent just insert the command (without adb shell) into an empty file and name it to install-recovery.sh.
After that push it to the device:
adb connect IP:5555
adb root
adb remount
adb push install-recovery.sh /system/bin/install-recovery.sh
adb shell chmod 0755 /system/bin/install-recovery.sh
adb shell reboot
You may need to add a
sleep xx (for me its 20 sec) to the beginning of the install-recovery.sh script to make it wait for the system to initiate completely.
And that's it.
Welcome.
