I am having exactly the same issue at the moment.
I've run the distance calibration dozens of times and it's failed the first part of the test each time.
i get the messages: "Calibration fail (not get a valid value)"
and: "The alsps min value exception!"
Was a fix found for this or should I be seeking warranty on my phone?
I got it through the kickstarter.

I have tried to calibrate under bright sunshine as well and had failure after failure. Customer service has offered to look at it if I ship it back via registered airmail, but that costs about 90 Canadian dollars and would leave me without my phone probably for months.
I'm wondering if maybe the sensor itself is easy enough to replace myself? I'm quite handy and willing to try anything to get this amazing phone functional again.

This issue did resolve it's self for me.
I have not had this problem again since.