1 - use Basic, not INS13 in Attitude -> Settings -> AttEstAlgo
2 - when using INS13 you get med orange LED flash then med blue LED flash (repeat) when sats>=7 and other things, the orange LED flash will go from medium to quick
3 - yes, but be careful to always export and import via USB NOT RF/OPLINK (a bug)
4 - thermal cal makes baro work without rise/ fall due to FC temperature change as it warms up (etc)
5 - don't play with aux mag sensor orientation numbers, you must KNOW what is correct and use just that. I2C aux mag needs 0,180,0 others need 0,0,0 this assumes that GPS/mag is mounted correctly. It does have a correct direction.