Problems adding functions to RamDisk

Other Hardware Storage
2 
    if (!vol.format(&ram, 256, 4, 1)) {
      Serial.println(F("format fail"));
      return;
    }

This says use 256 blocks of ram, allocate 4 blocks for directory, and cluster size of 1 block.

You probably should just use the defaults.

    if (!vol.format(&ram)) {
      Serial.println(F("format fail"));
      return;
    }

This will use all blocks, allocate at least four blocks for directory, and use a cluster size of one.