Ehnto

No, MAP is the most relevant for ignition as that is more closely related to combustion chamber pressure (ho much advance it needs).  MGP works better for the VE table look up.
But you are right, it is often nicer and more intuitive to have the same axes on both fuel and ign tables.  If you dont see large elevation changes in your normal use then its not going to matter - you can use either.  I often put MGP on the ign table, but it is relatively flat around my ways.

The settings overflow/underflow will be solved with a firmware update - basically it is just a scary warning that there is a setting out of bounds, it wont effect the way it runs.  
The re-lock thing sounds more worrisome, like some serious interference or something.  Does it have resistor sparkplugs fitted?

I had the same issue. Update the firmware of the ECU, that should solve it.

Anti static wrist strap.

https://www.antistat.co.uk/product/disposable-esd-wrist-band/

You're suppose to stay grounded while handling the ecu during the installation process.