  Motivated by a recent breakthrough transport experiment [Phys. Rev.
B.107.245423 (2023)] in Majorana nanowires, we theoretically investigate local
and nonlocal transport in Majorana nanowires in various disorder regimes,
correlating the transport properties with the corresponding local and total
density of states as well as various topological diagnostics. We find three
distinct disorder regimes, with weak (strong) disorder regimes manifesting (not
manifesting) topological superconductivity with clear end Majorana zero modes
for longer (but not necessarily for shorter) wires. The intermediate disorder
regime is both interesting and challenging because the topology depends on many
details in addition to the strength of disorder, such as the precise disorder
configuration and the wire length. The intermediate disorder regime often
manifests multiple effective transitions between topological and nontopological
phases as a function of system parameters (e.g., the Zeeman field), and is
consistent with the recent Microsoft experiment reflecting small topological
gaps and narrow topological regimes in the parameter space.
