Get dotlesscss to show compile errors

If the compile of a .less file fails with dotlesscss it will often just show a blank page. To make it show the compile error, just add a logger to the config (see answer by tony722).

This settings worked for me:

<dotless minifyCss="false" cache="false" web="false" logger="dotless.Core.Loggers.AspResponseLogger" />

See list of options here.