Very cute cushions, I would say:
pic 2 - Arenaria tetraquera
pic 4 - Arenaria alfacariensis
pic 3 - maybe a Draba (rigida?); have no idea about the first one
.
You can also try the elimination method and cross over the ones that are 'not' for sure: antennaria, androsace probably all, asperulas, edraianthus, erysimum, helichrysum.
Other opinions would be very welcome of course.