I've created a simple test to demonstrate pstorage store/load for 64 pages of 1024 bytes each. To allow 64 flash pages I set PSTORAGE_MAX_APPLICATIONS to 64. Each page stores an array of uint32_t sequential values 0-16383. After doing 64 store operations, it does 64 load operations and checks the data for expected values. The result is that blocks 1-23 return all zeros, block 24 returns partially expected results, blocks 25-48 return expected results, and blocks 49-64 return the values that should have been stored in blocks 1-15.
Demo is based on ble_app_uart begins by sending ble string "flashtest", results are output with printf.